TornadoBlog.org

May 30: Homeward

2011-05-29T20:48:00.000-07:00

Well, for various reasons, I have decided to call it a chase for this season. Our chase was successful during this nearly week-long period when the synoptic-scale patterns were favorable. We also made some bad navigational and tactical errors. More on that when I have time to contemplate the last ten days.

May 29: Cheyenne Ridge area of extreme se Wyoming/ne Colorado

2011-05-29T07:58:00.000-07:00

9:44 PM MDT Update: Well, my estimate that the convective inhibition would fade away by late afternoon was way off mark. We called it a chase at around 6:45 PM.

5:13 PM MDT Update...Sitting near I76 south of Fort Morgan or so, awaiting whatever might happen. Right now, not much.

The target seems too obvious...and I hope I am not deluding myself because I am in Denver right now. The models paints a very favorable picture for both supercells and a possible tornado along the Cheyenne Ridge this afternoon. Ahead of the deep trough coming into the Four Corners area under 40 to 50 knot 500 mb flow...the RUC has a surface cyclone correctly initialized this morning. During the day this intensifies and channels strong east southeast flow into Colorado bringing really high dew points for this part of the Plains into ne Colorado and then up the Cheyenne Ridge. Will 55 to 60 F dew points actually make it into this area, which currently has 40s? My guess is yes....as the foggy air all over this area currently has 50s dew points.

Upstream in the surface flow in KS are the 60+ dew points in southeast flow moving this way. The model takes the surface low northward and centers it in north-central Colorado this afternoon and I can't believe my eyes that it has surface southeasterly winds of sustained 20 knots or so over the region, and with a great angle with respect to the Cheyenne Ridge.

Throwing caution to the winds, because as soon as I point this out, the next run will evaporate it, I see the RUC breaks out precipitation there and has what looks like a supercell east south east of Cheyenne. As others have pointed out that starts out in the mountain convection around 20 UTC or so, and has a very good look around 22 UTC. I plotted a sounding and hodograph from the RUC for that location for 0000 UTC. Those are to the right.

While I'd like to see more turning in the hodograph in the lowest 3 km...it's pretty good. The sounding says that LCLs will be low too, but there are some CAPE-robber qualities in it. That elevated inversion was there in all the forecast hours, but was very strong in the initialization and systematically weakens. Finally, yes, this is all contingent on the fog clearing out. Not the initiation in the mountains though....that will happen. I'll wager the soundings evolve sort of like the one I have below, because the fog will have cleared out.

May 28: Two Possible Targets in KS--Went to Colorado...and Bust

2011-05-28T06:34:00.000-07:00

10:05 MDT Update: After sheparding Thom to the Tulsa Airport, I hooked up with Scott Landolt and company....targeting Colorado.

I decided to abandon my target areas because of tremendous capping (the warm air aloft mentioned below)....but much to my dismay...one of them would have had me reasonably close to the storm in Kingfisher County, Oklahoma, though, truthfully, I would have been further west and probably would never have gotten back in time for....what? Frankly, that storm looked good on satellite, but never did have a stunning look on radar. But I digress....

....decided to play that ever shimmering target of the Palmer Divide, which once again, when I got there, lost its shimmer. Will the Palmer Divide ever, ever produce a decent storm as advertised. I realize that rotating storm did develop a way down south...but what we were seeing along I70 looked to me to be layered clouds associated with forced lift of pretty stable air north of a warm front in the warm advection area.

I am certain enough about an early exit for me to have booked a flight for Monday. True, eastern Wyoming or ne Colorado beckons tomorrow....but I am not going to go way northeast on Monday, and after that all things go down hill and, frankly, the weather pattern in California looks to be more interesting later in the week.8:15 AM CDT. Awaiting the 12 UTC RUC. But the two other plays I see (besides eastern Colorado) are along the outflow boundary/quasi-warm front south of I70 (sort of north of Emporia and west to east from there, but mostly east) and the upslope area along the KS-OK border.

There is a very warm layer, or cap, pushing out from the desert Southwest at around 10000 feet. That will make storm initiation a real problem. But the models have a real moisture surge underneath that back towards the west around the mesolow in Oklahoma, and adequate moisture along the outflow boundary further north too. With lots of heating, getting storms to initiate may not be impossible...and if they can move back into that deep moisture, then a supercell or two is not out of the question.

I just dropped Thom at the Tulsa airport...and will be attempting to link up with Scott Landolt, Daniel Porter and Cameron Redwine later on.

May 23: Wall Cloud/Brief Tornado -- Okeene, Oklahoma

2011-05-28T05:28:00.000-07:00

This is a short video showing an impressive wall cloud/lowering near Okeene, Oklahoma on May 23, 2011. You'll see a brief tornado, we think, on the east side of the wall cloud as it approaches the road. The view is looking north. The video is shot by a point-of-view camera with no zoom, and the focus set at infinity. Thus, the wide angle makes everything appear very small.

May 24: Canton Lake/Fairview Tornado--Elephant Trunk/Sinuous Funnel Stage

2011-05-27T21:43:00.000-07:00

Again, this is the download from our HD point of view camera. It cannot be zoomed. I will download footage from my digital video cam when I return home.

The Canton Lake storm was rated EF3. However, we saw its first stages (below) and this stage. There must have been translucent connections to the ground for the first stage and a dramatic multiple vortex or suction vortex with this stage in order to account for the damage. The visual evidence is not compelling from this video.

May 27 -- Central and North Central OK

2011-05-27T09:53:00.000-07:00

6PM CDT update: we are definitely in moist flow up here in Guthrie. Unfortunately, the stratocumulus field is squashed. The inversion is holding, at least to this point. Models still suggest something happening between 7-8PM CDT....with sunset around 8:30 PM...not much time to observe a storm...and we do not chase at night.
_____________________________

A warm front/dry line/cold front triple point should move into the area west of Oklahoma City this afternoon. There is more than adequate shear for supercells. Here's our target.

Some of the issues include whether adequate deep moisture will get back into the target area if the triple point is there. The models are suggesting that convection should outbreak in the area of slightly southwest of Oklahoma City to Guthrie to Ponca City and slightly eastward in discrete cells at around 4PM local time.

We are currently (1:54 PM CDT) in Gutrhie, Oklahoma in Rick's Fine Chocolates and Coffee Shop. Besides the great coffee, there is a good wireless connection here.

Grove OK Tornado May 22, 2011 -- Very Brief Glimpses of Stovepipe

2011-05-26T13:01:00.000-07:00

This was very frustrating...the tornado then evolved into a fat stovepipe shaped thing to the left (east) of the road, about 4 miles away. But the trees only allowed brief glimpses. Remember, the Point-of-view camera has no zooming feature.

May 22 -- First Grove Tornado

2011-05-26T12:57:00.000-07:00

This is from our windshield mounted camera. No zooming possible and no rotating field of view (beyond 20 degrees or so). We were in forest and hills...the tornado is right on the road directly ahead of the camera and then slightly to the left of the road. We were desperately trying to find a place to stop with an unobstructed view.

May 26: National Weather Center

2011-05-26T07:31:00.000-07:00

Thom and I are taking this down day in Norman, OK. He's never seen the National Weather Center (dubbed the "Intergalactic Weather Center" by Chuck Doswell). We'll also visit with Chuck and Vickie, Mike Foster and others, and perhaps see a movie. Tomorrow there is a risk of supercells in central Oklahoma....so we are staying in place. Thom is changing his outbound flight to Tulsa or Oklahoma City.

First Hand Account of Joplin Tornado by Roger Hill, a Colleague of Mine

2011-05-25T21:19:00.001-07:00

Adding pictures to older Blog Entries...be sure to check below

."...Well, might as well throw in what happened to us this day, but PLEASE understand what happened was TOTALLY unintentional.

We started the day in Tulsa and drifted north into southeast Kansas. Was on the pile of junk cluster of cores spewing outflow from Parsons, through far southeastern Kansas. Several new cells formed south of the outflow boundary from the storms north of Columbus, and as they developed, they crossed into cold air, spun for a few minutes and then became hailers. Near Crestline, KS we encountered a cell that produced near baseballs on us. It had a nice wall cloud, but quickly crossed into the cold outflow air and weakened. Seeing the storm that would eventually become the Joplin wedge producer develop, we moved east into Joplin, with intent to drop onto 44. We came into town on Mc Arthur Dr, and then turned south onto 71B. This was about 20 minutes before the tornado formed. Running low of fuel and many tour guests in need of a restroom stop, we stopped on 71B. I just happened to look at radar and see the storm right turn along the OFB and develop a strong hook. We ended up blowing off the gas/restroom break and headed south to get out of the way in case the supercell was producing a tornado.

As we drove south, the notch was becoming visible as rain curtains were wrapping intensely on the east side of the now wedge. We were directly in the path of this monster and I knew we were in serious trouble if we didn't get out of the way. We were now crossing 44 Business and heading south toward the I-44 corridor and trying desparately to get out of town. Traffic was oblivious to the situation developing, and there were NOT any tornado sirens to be heard! As we crossed 15th street, numerous power flashes occured just to out west. People were walking around and not paying any attention to what was going on. We yelled out to take cover NOW, and several laughed at us. Two vehicles were next to us at a traffic light and we told them what was going on and they totally ignored us. As we crossed 20th street headed south, things got worse than I have ever witnessed. Intense rapid rotating rain curtains were only a few hundred yards west of us, and all power went off. Traffic lights ceased working and we knew we had to take things into our control and blow threw them. We weaved in and out of cars with our flashers on as vehicles stopped in the middle of the road and watched. Cars were going northbound and I shutter to think what happened to them. We honked, yelled out to any vehicle or person WALKING up the street to take cover and then had to get south. As we approached 29th street rain curtains blew from southwest to northeast and chunks of debris started falling as continued power flashes were occuring extremely close to us. Westerly winds picked up to at least 80 mph as we weaved in and out of traffic, finally approaching the interstate. We turned east of 44 and then south on 71. One of the most intense moments of my life and shows how quickly things can evolve when you least expect it! Jeff P's video was extreme and he was not far from us, but he was there intentionally. I was not.

Later we witnessed the cone near Southwest City, and then a stovepipe west of Siloam Springs that damaged a bunch of mobile homes. Absolutely insane day, one I will never forget.

An absolutely horrific experience for the poor souls of Joplin. A good friend of mine was the manager of the Pepsi plant there and it was totally leveled, with a few of his friends now deceased. ...."

Update on Tornadoes: May 22 and May 24

2011-05-25T20:45:00.000-07:00

May 24, 2011 - Canton Tornado

The Canton tornado (picture reposted here) of May 24, 2011 has been rated an EF3 tornado. We also have learned that the first video we took (to be posted later) may have been the tornado that caused the most damage.

May 22, 2011 - Joplin Tornado

We have included a map showing the track of the Joplin tornado, now rated EF5. The red arrow shows the track of the tornado based upon NWS surveys. The black squares represent our position (by GPS) at 5:48 and 5:50 PM. The tornado first formed at 5:41 PM and lifted at around 5:53 PM. At the time it lifed, we were stopped by the heavy precipitation and hail in the hook curling around the storm's southside. If we had continued through the hook, we likely would have had a very close encounter with the tornado at about the time it was dissipating.

More sobering for us, is that we waited about 10 minutes in Miami, OK before moving northeastward, photographing a funnel cloud. If we had not done that, the hook would have not been crossing the freeway when we got to Joplin...and, worse, we likely would have been well into the city of Joplin when the tornado was in the city.

May 25: Holding Steady in Oklahoma

2011-05-25T10:45:00.000-07:00

Today is a down day for us.

We've had a change in plans. Although there is a reasonable pattern for severe storms in eastern Wyoming and the Nebraska Panhandle tomorrow....there is a far better risk for organized convection and supercells in the eastern half of Oklahoma on Friday. Right now, the plan is for Thom to change his flight to Oklahoma City or Tulsa for Saturday morning. We'll make a final decision about that tomorrow morning. But tonight and perhaps tomorrow we'll be staying in Norman.

This gives Thom a chance to see the National Weather Center (aka Intergalactic Weather Center) and us a chance to visit with Chuck and Vickie.

Meanwhile, we had an illustration yesterday of why Tornado Warnings, even if very timely, don't work very well anymore out here. The server at the Starbucks in Enid yesterday told us that when she hears a Tornado Warning she heads outside to check the sky. Mostly, that would be OK, of course, because most tornadoes are small, and the tornado warnings are kind of general enough...in cities they turn on the sirens to warn the whole town.

In the case of Joplin on May 22, the tornado was so large and fast moving that any action besides taking cover was probably fatal. I am trying to get permission to repost what one of my storm chase colleagues related about his experiences in Joplin that day to illustrate.

May 24: Canton/Fairview Tornado

2011-05-25T09:27:00.000-07:00

We were off to a vigorous cell about 70 miles southwest of Enid. We'll post some pictures right away of the small elephant trunk tornado that formed on that storm as it approached Canton and Fairview, OK.

Later, we sped eastward to get ahead of more supercells passing across I35 and managed to see the mesocyclone left behind from the Guthrie tornado...and may have seen a wedge tornado wrapped in rain near the town of Hominy. More as time permits.

Frist Cells---

2011-05-24T12:19:00.001-07:00

we are leaving Enid. There is a very healthy looking cell north of I40 moving into west central Oklahoma.

May 24: Central Oklahoma

2011-05-24T09:40:00.000-07:00

Adding pictures to older Blog Entries...be sure to check below.

We are currently in Enid, Oklahoma. The students reading this blog will recognize this morning's Oklahoma City sounding as an example of the so-called "Loaded Gun" sounding. In fact, the sounding will be altered by afternoon not only by surface heating but by increasing dew points. This makes the potential for this sounding even more significant.

The morning's surface map has many incredients in place...a triple point in south-central KS....with a dry line extending south. A warm front moving through Oklahoma into southern KS. However, the models portray some forecast issues for foci. One model moves the triple point north and would have the risk further north...while another model has the best play of incredients in the southern portion of Central Oklahoma.

Unfortunately, the models suggest that an outbreak of major tornadic supercell over Oklahoma and southern KS perhaps into Missouri. The parameters are in place for strong and violent tornadoes today...and perhaps several of them.

The OKC and Tulsa Metropolitan areas will be threatened this afternoon.

This is fresh after the awful destruction that the Joplin tornado caused. The death toll is over 150 now, and the indicaitions are that this may have been one of the most destructive tornadows in the record of the National Weather Service.

May 23: At least ten funnel clouds/possible tornado

2011-05-23T14:40:00.001-07:00

Thom taking a picture of what might be a developing tornado near Kingfisher

Thom and I were eating lunch in Fairview OK (about 60 miles northwest of Oklahoma City) watching the first Fairview storm develop. It was already rotating soon after it had an anvil, complete with an elevated horseshoe base. Right away, it was odd....on the southeast side of the updraft tower was a very pronounced laminar funnel...not from the rain free base. There were four other sinuous funnels, elevated bases...but with large extension from the forward flank tower. We saw yet another funnel cloud with this storm after it backbuilt about an hour later, and a tornado warning appeared a short time after.

Nice looking wall cloud northwest of Kingfisher at around 8:15 PM CDT.
At this time the radar showed a hook echo.

I'm not sure we were witnessing splits. It seemed that the process was more like train echoing... I think the weak700 mb winds were allowing precip to wrap into the updraft area....causing outflow surges back against the shear. The net effect was that the updraft area appeared to stay near Fairview.

Two midlevel funnels near Fairview

Look closely---a sinuous midlevel funnel

Panorama of one wall cloud, looking east, during one cycle of the storms

I don't know how many times we circled around these storms back west, then east, then back west. There were some very impressive ground scraping wall clouds that then became forward flank shelf clouds as the outflows crashed through and a new upraft score redeveloped northwest. Anyway, after many such cycles, the last one we saw near sunset was the best....and it had a real nice hook...with TVS signaatures showing up pretty continually for an hour or so....but though we were sure we saw "near tornadoes" on the wall cloud...the thing always looked outflow dominated with a ragged base. We were pretty sure we pushed through a spinup or a large gustnado...though it may have been a weak tornado.

The pictures at right illustrate some of the funnels we saw. The first picture at top shows the wall cloud associated with the hook echo shown on the radar plot (at bottom right). We think it may have produced a very brief tornado to the north, and as pointed out above, as we drove south we passed through a weak circulation (resembling an early spinup of a tornado) coming across the ground. It may also have been a gustnado.

All in all, a nice day of chasing.

Another midlevel funnel near Kingfisher

Under the flanking line/shelf....very ominous.

Hook Echo/TVS from GRLevel3 for final storm of the day.

This was the first funnel of the day on the southside of the updraft base of the storm developing near Fairview

May 23: West Central Oklahoma

2011-05-23T09:51:00.000-07:00

Our prelminary travel target is west-central Oklahoma. Details follow. hings are a little muddled today because of the anemic 700 mb flow. As others have pointed out, the CAPE field is outstanding....and there's a nice southwesterly 30-40 knot 50 mb flow that, with surface southeasterly flow does give 0-6 km bulk speed shear values around 40 knots. There is a sweet area in the models between Clinton and Enid or so that has barely adequqte surface flow of 15 knots....and the hodographs in those areas are strongy looped in the lowest 3 km.

But the anemic 700 mb flow suggests core dumping in the updraft areas....however.....with proper storm motions, southeast, one can get adequate storm relative flow even at 700 mb (a lesson underscored by the Sheridan Lake and more spectacular Campo events last year).

And then, there is that outflow boundary/ies. We are just leaving Tulsa on the backside of that. Some of the cases the last several days illustrate how important those can be on days with marginal shear. Thom and I are still a bit awed by what happened yesterday....when I posted our summary yesterday evening I was unaware that so many people lost their lives and that the storm so devastated Joplin. To think that we were 10 minutes or so and a hook echo crossing the freeway away from getting into that is sobering.

Anyway, we are targeting the area southwest of Enid today, unless something changes in the observational fields as we are driving.

May 22: Joplin

2011-05-23T06:44:00.000-07:00

We are just rousing after a very late night...by the time we got into Tulsa, had dinner and got back to the motel it was 12:30AM. The initial reports we had about the Joplin tornado we got when we got back on the turnpike on the way back to Tulsa. The toll taker told us that the tornado had some fatalities, and the hospital there was badly damaged. But this morning, learned from colleagues that the Joplin tornado produced much more damage and casualties than the reports last night indicated.

Again, Thom and I were fortunate....had we not stopped in Miami OK to watch the funnel develop there, we probably would have been moving towards the developing hook northwest of Joplin 10 minutes earlier. That 10 minutes meant all the difference as the hook was enveloping Interstate 44 by the time we entered the western parts of the city. This the radar image we got just before we drove into that very broad hook and then stopped.

We need to get more details on the Joplin disaster.....the NWS had issued warnings long in advance of that storm moving into the city. The storm was the ultimate endproduct of the storms that formed in se KS, which were tornado warned all afternoon. When we dropped south to Miami OK, Joplin was already under a tornado warning. So the sirens had to have been on, and the emergency services of the city in full action long before that tornado came into town.

Now we have leaned that the tornado was at least a half mile wide. Although the sirens were turned on 30 minutes before the tornado hit (and again 15 minutes before), there's not much one can do if the tornado was a high end event...besides leave the path. Apparently, just ahead of us on Interstate 44, 18 wheelers were lofted from the freeway, and homes were "slabbed" (according to reports from some colleagues who got to the town before the hook moved across the freeway). By the way, one of these chase colleagues is a doctor who today is serving as a volunteer for emergency services in Joplin. Also, one of my colleagues was there with a tour of individuals....they helped emergency services in search and rescue.

In any event, this is one of the reasons we prefer to chase in the western Great Plains. The population is sparse, and these sorts of sad things can't happen for supercells churning up the grassland. So the elation we feel at the success of our chase yesterday is tempered by the knowledge that the storms we are chasing can produce awful effects, like earthquakes, volcanic eruptions and tsunami.

May 22: Stovepipe Tornado, 2 Funnels, and Possible Second Tornado

2011-05-22T22:00:00.000-07:00

Short: Thom and I were on the Independence KS storm as it cycled. We tried to stay with it and got to Joplin MO about 10 minutes before the tornado came through, but were cut off by the hook.... We dropped back west and caught the second Grove tornado as it first had a debris cloud and then became an impressive stove pipe tornado. (We didn't get much photograph because of the forests and fast developments. But once we have time to download it, we will post it here).

Long: Thom and I saw one major tornado today, two funnels two thirds of the way down, and another possible tornado near sunset. We targeted the area northeast of Bartlesville, and went north to the first Independence flare up. It cycled...ingested a few other storms...looked good for a while, with a couple of wall cloud attempts, and finally an HP bears cage bearing down on Coumbus....but as we dropped south, the storm had two right flank developments...so we got to Miami OK...only to find the southern most storm produce a laminar elephant trunk two thirds of the way to the ground. Actually, the base of that was obscured in the buildings and trees north of town....so it could have been a tornado.

The Columbus storm amalgamated with the two cells to the south to produce a monstrous hook just on the Missouri border northwest of Joplin. So we got on I44 and got into the western portions of Joplin, only to be gobbled by the hook. The heavy rain and large hail (about half dollar stopped us in our tracks. The storm was extremely electrified...it's been years since we've seen such great continuous show of CG.

We got on I44, fortunately, just at the right time. I don't know how lucky our stars were today...because the troopers closed I44 in both directions just after we started back to Miami. Ominously, lots of emergency vehicles goint northeast...many many of them. As we turned onto the Interstate, Thom spotted another funnel hanging 2/3 of the way to the ground from the next cell to the southwest. But we saw the better looking storm south of Exit 302 on the Interstate. As we came into Grove, and turned south, and crossed the bridge, a large laminar funnel was dancing over the road, about 4 miles south...and then corkscrewed sideways, and sinuously came to the ground, producing a gout of debris. Frustrating was the poor visiblity preventing good photography of the thing as it moved eastward and became a broad stovepipe about 5 miles northeast of Jay. But our ability to get to the east-west road was thwarted by the damage path of the tornado...the troopers had closed the road about 1 mile north of Jay. We had to get back to Grove and then move east, but yet another supercell was on the way.

We know that the subsequent storm probably had a tornado south of our position...but, with the road closed, we were stuck in the core...under the roof of a gas station....with GRlevel3 showing a TVS and strong mesocyclone on top of us. We had to abandon the chase there, but as we moved back to I44 yet another supercell came rolling up the boundary there....and in the distance we saw a gout of dust extend from the ground up about 1/3 to cloud base under the updraft base just after sunset....with mid level stingers extending into the updraft core from all sides. Not enough light for pictures, though.

All in all, a terrific day, except for the sad news about Joplin.

We are overnighting in Tulsa, and found a great German brew pub with home made Bratwurst!!!

Looking at the progs, I must say the next two days' patterns look to be very prolific supercell producers. We think we'll be in the eastern TX Panhandle or SW Oklahoma tomorrow and then south central KS the next day. The patterns are "synoptically-evident" and liable to have strong and violent tornadoes too, like today, in parts of the region.

May 22: Stovepipe Tornado, 2 Funnels, and Possible Second Tornado

2011-05-22T19:39:00.000-07:00

Brief Report: Saw large stovepipe tornado, along with 2 funnel clouds 2/3rd the way down and possible 2nd tornado in NE Oklahoma. We were in Joplin MO but did not see this tornado since were were cut off by the hook. More later.

On the way to Nowata, OK

2011-05-22T10:45:00.001-07:00

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Location:Ponca City,United States

May 22: ne Oklahoma or north Texas? It's ne Oklahoma!

2011-05-22T06:34:00.000-07:00

We are sitting in Perry OK with a Noon checkout....and are debating two targets....our original one near SPS and east (where both the NAM and the latest RUC forecast large values of CAPE) and the area of ne OK, where the RUC (but not the NAM forecasts nuclear bomb CAPE of 7000 J/kg).

Next looking at the forecast soundings....the NAM has CIN for ne Oklahoma and very little CIN for the southern target...and the RUC has CIN holes in both locations. Looking at the forecast hodographs there would be no contest. ne Oklahoma has dramatic loops with nearly 30 knots of low level shear in both the NAM and RUC forecasts. Looking at those hodographs, I see the shear vectors nearly at right angles for 0-0.5 to 0.5 to 1.0 km!!!! There are dramatic turning of the shear vectors in the hodographs for the southern target too....but the deep layer shear is 36 knots (0-6 km) for the southern target and 46 knots for the northern target.

By the way, the hodograph was the key to understanding some of what happened in ne KS yesterday. I am trying to get myself from just assuming that surface winds need to be southeasterly....they don't, because the hodograph is the key. A sw surface wind (wiht adequate CAPE) can give a wind profile favorable for rotating storms if all the winds are shifted to the right on the hodograph. Then the low level shear becomes important....as some found out and pointed out by action yesterday, outflow boundaries can augment the anemic low level shear profiles in some cases....clearly that's what happened in ne KS yesterday. Too bad I couldn't put my own actions behind those nice sounding words....!

Anyway, we have an hour or so before checkout, but our provisional target is very close by....Tulsa and northeast. The last plot at right shows the position of the cold front and dryline this morning and projected for this afternoon.

The white arrow shows the jet stream's position this projected for this afternoon, and the red arrow represents the axis of the tongue of high dew points and CAPE for this afternoon. The green shading shows dew point contour channels starting with 60F, then 65 and 70F. The semi-transparent cold front and dryline indicates the forecast position of the dryline and cold front this afternoon. It's been a while since we've chased a very very high CAPE pattern that also has favorable shear.

By the way, our runs in Perry today were absolutely miserable. :-) The hotel is about 1.6 miles in a straight line down a multi lane street with no shoulder or sidewalk from the town of Perry. We ran that way because there was a park there that seemed a good destination. We forgot to factor in the howling winds which aided us on the outbound, but were in your face on the inbound portion, which was slightly uphill. Combine that with the inboud being slightly uphill transformed what should have been a pleasant jog into a real chore. I truncated my run at 4 mlles, but Thom managed 7 miles....and it wasn't fun. On the other hand, it's nice to keep up the routine of working out each morning somehow. Tomorrow, if possible, I'll find a gym.

May 21: Convective Initiation Soon....and Giving Up Too Soon

2011-05-21T13:33:00.000-07:00

Here's a shot of the developing cumulus field north of Wichita at 3:30PM CDT. The cumulus were making initial attempts to develop.

And they explosively developed, as we watched, just west of Emporia, KS. But, during the 45 minutes or so we watched...the anvils became diffuse, the radar presentation was not convincing, so we decided to drop south to our overnight location in Perry, Oklahoma, since our initial target on Sunday appears to be the Red River area around Wichita Falls TX.

Alas, the storm, as it approached Topeka in northeastern KS became an intense supercell. As much as we can make of it from the radar information, it must have crossed over a boundary, because it really suddenly developed a hook, and had Tornado Vortex Signatures consistently for the next hour. Some video we were able to see indicated some very well defined funnels associated with it. I'm trying to communicate with some colleagues who stayed with the storm to see what kind of tornadoes (and if tornadoes did indeed occur).

May 21: Into Southeastern KS

2011-05-21T10:29:00.000-07:00

What we see (from the RUC) for this afternoon are soundings with very little CIN and ~3000 J/kg around Independence, KS, for example. Yes, the surface winds are not forecast to be southeasterly, but it turns out that south southwesterly winds actually give a very good hodograph (see right, for Independence KS this afternoon). That anticyclonic loop is very dramatic between 0-3 km, with nearly 90 deg turning of the wind shear vector. The 0-1 km shear is nearly 30 knots! I don't see any evidence of weak shear, or unfavorable shear profiles and haven't for any runs of the models the last 12 hours. It's true that the NAM had some funky turning of the shear vectors for several regions in its 0000 UTC run, though.

It's hard for us to ignore 3000 J/kg and a favorable shear profile, just 100 miles or less from us today. I also think there will be action along the Red River tomorrow....so at least that area is in range, even if we get as far north as Emporia today. So our provisional target is centered near Independence, KS.

Preliminary Target for May 21--Southeastern Third of KS

2011-05-20T20:59:00.000-07:00

Thom and I are considering options for tomorrow....and, I must say, I think the pattern looks a bit better tomorrow than the pattern we had today.

There is a wedge of high dew point temperatures and CAPE, with, according to the WRF-NAM, little CIN, from southeast Oklahoma through extreme eastern KS to the northeastern third of Kansas....underneath very decent 500 mb flow. In fact, the surface wind to 500 mb crossover is forecast to be much better in those areas than the best we had today. So good, that the forecast 0-3 km SREH values are very enticing...where they are coextensive with the better instability values.

I plotted forecast soundings and hodographs for that area, and there are some striking anticyclonic loops in the lowest 3 km over se KS and up through the Topeka area...and also down into se Oklahoma. The soundings have a very steep lapse rate in the EML which explains why the forecast sbCAPE values are more striking for those areas tomorrow than the same surface temps and dew points produced today in parts of KS.

I think we'll be rargeting the area east of a Topeka-Emporia-Tulsa arc tomorrow afternoon. I'd rather not go down to the tropical rainforested hills of se Oklahoma, but I will if the pattern resolves out better in the morning models and obs; so that arc may spread south of Interstate 40.

Right now it's a go for us. The prospects seem much better in those areas tomorrow than anything we had today, and we saw interesting storm structure today.

Forming Wall Cloud--Three Storms, Briefly Supercells Probably

2011-05-20T16:42:00.001-07:00

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Thom and I were drawn to the target in the vicinity of Pratt, as explained in our forecast posts. The first convective initiations produced a discontinuous line of multicells from near Russell to just south of Pratt. We holed up briefly in Great Bend, trying to see if the northern weak cyclone would develop some backed flow near I70, hoping to pull the 65F dewpoints back west...but that didn't happen.

But the weakly backed flow near Pratt was still ongoing, and we noted some tendency for the linear cells back there to break into more discrete ones. In fact, we saw three cells there that had supercellular structure characteristics. Each of them produced a lowering/wall cloud that briefly did not look shelfish...but mostly just looked like outflow features. But the few minutes for the first three storms that wall clouds developed there was some interesting structure...including inflow tails that extended far north as roll clouds, sculpted updraft towers, and some high-based, perhaps shear funnel clouds. Each wall cloud or lowering had only weak signs of rotation...and most of the time looked ragged. But one of those latter cases produced a feathery looking large lowering with blocky outline (but was not solid at all...imagine a bunch of feathers jammed together hanging downward and flaring outward).

We briefly dropped south to watch a fourth storm....but decided it was going to undergo the same fate ultimately. Actually, it did briefly look good on radar when we got to Hutchinson. But by that time we had committed to pulling in for the evening.

We weren't expecting much of this day...but frankly it was fun, and we saw some great storms and cloud features.

Organizing Supercell

2011-05-20T16:40:00.001-07:00

Nice nontornadic

storm forming.....
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Location:View St,Oakland,United States

In Great Bend at 3:53PM CDT...

2011-05-20T14:00:00.000-07:00

We are temporarily in Great Bend. We are now considering moving towards a vigorous cell that is showing signs of rotation now near Greensburg. The radar image included here is recent....the little icons on the roads are the position of other chasers.

A Mess of Storms Today: No Significant Focus, and Limited Tornado Potential

2011-05-20T10:43:00.000-07:00

Thom and I are sitting in a grungy Ramada Inn in Salina. Right now we are thinking about the area southwest of Pratt into northwest Oklahoma this afternoon. As Roger points out, the deep layer shear is expected to be fine there this afternoon. I'm afraid that the low level shear looks very weak....but that is where the models suggest sort of a dry line bulge, perhaps a weak surface low to amplify surface flow. The CAPE field appears adequate. Not a very good setup, but it's what we have got to work with.

Complicating things a bit on a day that is already pretty much of a mess...is that the best forecast hodographs are around Topeka. But with lots of CIN left over from the day's convection. So that area is, of course, out.

I still like the area between Wichita and Pratt or so....the RUC shows that weak low in sw KS and nw Oklahoma. If we can get the winds to stay backed at the surface with some decent flow....then the very good 500 mb flow of 45 knots or so SW winds COULD yield a supercell or two. There are outflow boundaries sloshing around too that might add a focus and also a source of low level solenoidal vorticity that could be tilted into the updrafts.

There are so many CONS today, it's pointless to list them all. And it looks like there might be a sucker line of storms that develop early. Both the HRRR and RUC, with their high FAR,suggest isolated cells west of Pratt around 22 UTC or so, after that other line goes through.

Fortunately, we don't have to go far today, as we are currently in Salina. Right now, our target is around Pratt. But we might hang around a bit in Salina to see how the wind fields resolve.

Several energetic storms...

2011-05-19T20:36:00.000-07:00

Thom and I got to Hays about the time that the tornadic storm north of Russell had a beautiful hook...but it was also moving into colder air. It was part of a discontinuous line of storms extending from north of I70 to about 40 miles south. There was a break in the line on I70, and our intent was to punch through to the other side and then drive north to either the first cell or the second one that now was tornado warned. But, the area filled in, and we had a half hour of driving through torrential rain....with the GRLevel signal dropping out, and also Mobile Threatnet missing every other scan. By the time we cleared the line...almost to 20 miles west of Salina, the first storm had croaked, and the second one was a gigantic HP mess.

We kept our eyes on the Pratt area...because the bubbling cumulus field down there seemed sure to erupt. We stayed with it as it was producing strong mesocyclones and tornado warnings near LIncoln. We saw some supercellular structures embedded in the rain, but nothing too dramatic. We also dropped down to the next storm to cross I70....that developed a hook...and parked ourselves and stayed with the inflow notch for a half hour or so....but the inflow base looked ragged and never showed much sign of rotation. The radar image shown above shows the mesocyclones and the hook (as well as Mobile ThreatNet can depict it). The yellow range rings really are centered on the GPS location of our car (with the rings at 5 mile intervals). Note that we were in "the" location to witness any tornado....but it was not to be.

We soon gave up and dropped south to Salina. All in all, kind of a waste of the great potential this pattern had.

Onto west-central Kansas

2011-05-19T11:18:00.000-07:00

We arrived...and picked up our vehicle...a Chevy Equinox. While driving east to the target (still basically the same) we are trying to setup the computer, MIFI, GPS antenna, cell phone signal amplifier and making sure the software is operating correctly.

Southwest KS is clearing out, and moisture is coming northward through Pratt towards Interstate 70, which we are on. The target is in that general area shown by the box on the surface chart to the right.

Onto the Great Plains

2011-05-19T04:38:00.000-07:00

As we ready for departure to Denver, our target has not shifted. The wave cyclone currently in southwestern KS will shift northward with the warm front near I70. We are targeting the area south of Russell, KS, where forecast hodographs have long length.

The hodograph also has large 0-1 km shear values.

More as time permits.

First Day Target --- More or Less Unchanged

2011-05-18T09:18:00.000-07:00

Just updating our target on our first day out, tomorrow, Thursday 19 May. We depart Oakland on a 6:10 AM flight to Denver. Given the time change, the flight is scheduled to arrive 9:45 AM MDT. There is a strong jet stream present extending from California to the Plains (see post below), so it's possible we'll get to Denver a bit early.

As you can see from SPC's Day 2 Outlook, the area we are targeting is now within SPC's outlook range. The red area encompasses the area in which there is a larger than 30% probability that a severe thunderstorm will be within 25 miles of a point.

Also note the hatching. This indicates that within that area there is an enhanced probability that some of those storms can produce high-end severe weather events (EF2-EF5 tornadoes and/or Hail >2" diameter and/or sustained winds 74 mph or stronger).

Once tomorrow's convective outllook passes into the Day 1 range, they will be honing those risks. But, we feel that the greatest threat for tornadoes is from the western tip of that red area south through sw Kansas and into the extreme northwestern area of Oklahoma, given the buoyancy and shear fields. Some of the parameters related to rotation production in storms are at the extreme high end of their ranges (climatologically speaking) for that area, with the largest values in Kansas.

This means that we will have to get the car setup quickly. A lapstop stand with power inverter, three antennae (onboard radar, GPS, and cell phone amplifier) need to be immediately functional so that we can get data as we are driving...and we need to be driving quickly. That risk area looks close to Denver on the above map, but there's still at least 200 to 300 miles or more of driving we need to do to get into the target area close to initiation time, which is liable to be around 4PM local time.

Storm Chase Trip 2011 -- In to the Great Plains, May 19th

2011-05-16T10:12:00.000-07:00

Well, it's hard to believe that a year has gone by....but here we are about three days before our trip into the Plains. The long range forecasts have been showing a favorable pattern for the first week or so of our trip.

The first graphic here is the composite (average) of 500 mb weather patterns for similar weather maps at this time of year in the past....it shows a fairly dramatic trough in the far West, setting up a favorable jet stream pattern over the Plains.

The dates shown on this figure indicate the best matches from past years, by year and date. We won't try very hard to look at that, because some of those dates include some very significant tornado events.

We'll be posting each day, and probably on the fly during the day, as we can now post images via our cell phones, and we'll have live access to the web in the car. We're looking forward to this, our 26th storm chasing trip....gad...how time has flown. Meanwhile, Thom will be posting updates to his WildGeeseChase.org blog. That's the real story behind the scenes....

The pattern on the day that we arrive in Denver, May 19th, is setting up nicely for some severe thunderstorms in north central and central KS. So our target will be the area from Salina back west to Hill City or so (of course, to be adjusted as approach the time of our departure). The map shows our target as a blue box, and you can see we will be at the intersection of a dry line, cold and warm fronts...often called a "triple point" by storm researchers.

I have plotted a sounding and hodograph for the region between Hill City, KS and Salina for around 6PM CDT for Thursday. The red area shows the surface-based CAPE (the region where an ascending air parcel will be warmer than its surroundings and will freely loft). The hodograph is very interesting, as it shows that the low level wind shear will be quite strong, 20-30 knots underneath a very strong southewesterly jet. If this profile develops, then storms will rotate strongly, and the low level shear tells us that isolated storms are liable to become tornadic.

June 2: A Bit of an Early Exit

2010-06-02T17:12:00.000-07:00

I am leaving the Plains about three days early. The pattern is going down to a large extent for tornadic supercells for a few days, so there is no point in sticking around.

The trip was successful in terms of both seeing tornadoes and good photographic documentation, including video, for one of those days. That particular day was one of the best that Thom and i have had together, and ranks with two days in 2004, one each in 1999, 1997, 1995 and 1990.

There were frustrations, including some bungled navigation (which led to incomplete documentation of tornado day 2), too much hemming and hawing about drifting to northest SD on the first tornado day, leading us to miss the biggest tornadoes.

The missed major tornadic supercell on May 31 in se Colorado may make an interesting case study. That storm became a prolific tornado producer. But it occurred in a totally inadequate deep layer shear environment. Only a very odd storm motion, given the wind profile, produced an environment relative to that storm that supported a long lived supercell.

There was no question that the low level shear could spin up a tornado as long as the storm remained existant. That latter issue was one Chuck and I have debated with our other case partners. If we are to learn from this episode, it may be important to go back and look at the radar to see the true storm motions, and get some prxoimity sounding and hodographs.

Whether by skill or my luck, those that chose that target were rewarded, and I certainly hasten to congratulate them. It would have been one of the best tornadic storms that Thom and I would have witnessed, if not the best.

Such is the life of a chaser.

But, we'll be back next year. These trips are always learning experiences. They are also humbling, for when you think you are riding a fast horse to success, the next day, you can be bucked to the ground.

Thom and I thank all of our chase partners....Scott Landolt, Daniel Porter, Cameron Redwine, and Chuck and Vickie Doswell. It was great....

June 1: north-central to east-central KS

2010-06-01T05:48:00.000-07:00

Preliminary target is somewhere betweeen Topeka and Salina. We spent the night in Hays, KS, and noted that the forecast sounding and hodograph for the Topeka area (and a 75 mile diameter or so), is supportive of not only rotating storms, but tornadic storms.

But as the day progressed, it was apparent that the area with the best potential for tornadic storms was "capped", meaning that convection was inhibited by a warm layer aloft that was not eliminated during the day.

So we drifted north to play storms forming on the warm frontal boundary, and still hoping that new storms might form on the curling moisture band back west along and just north of I80. But while a couple of those storms briefly became supercells, they were rapidly undercut by the cold air north of the boundary.

So we ended up "blowing off" this day with great potential. Cameron and I then went west to spend the night in North Platte, which was an easy drive into Denver for my 7PM flight.

May 31: western KS

2010-05-31T10:35:00.000-07:00

We are currently in Goodland, just in a wait and see mode. There is a disparity between the RUC (out to 12 hr) and NAM-WRF models (goes out to 84 hours) in the view of where the focus will be today.

Both models suggest wind profiles favorable for rotating storms, and both models suggest that such storms will be briefly rotating in the south and long lived in the north. The difference is that the NAM suggests that storms will NOT initiate up this way, and the RUC suggests they will.

Anyway, we are holding at the Holiday Inn Express in Goodland, and watching the moisture fields/dew points as they evolve today. If they evolve in a way that suggests the RUC is correct, we stay put. Otherwise we drift south.

Tomorrow, the focus will be anywhere from southwest Nebraska to southeast Nebraska, and then the pattern goes down. So I am departing the Plains on Wednesday, but just in case we are pretty far east at sunset tomorrow, I changed my flight to Wednesday at 7PM from Denver International Airport. That would give me all day on Wednesday to drive back to Denver, if we are really far east.

And our forecast area never did get the moisture return forecast by the RUC. Not only did storms not initiate in our area, but a single storm, essentially, did initiate in the southern target, about 175 miles southwest of us, on the Raton Mesa.

That storm became a cyclic, repetitive tornado producer. Congratulations to all who made the astute decision to be in that area in advance. This is a storm worth studying. Evening hodographs verified that 0-6 km shear should NOT have been adequate for long-lived supercells.

May 30: Down Day--Heading to Goodland

2010-05-30T12:52:00.000-07:00

After watching some storms croak south of the boundary in northwest-central Nebraska, we put in for the night in North Platte. Since Sunday will be a down day, we are heading for Goodland, to be in position for what appears to be a chase day in the southwestern quadrant of Kansas on Monday.

Tuesday also looks like a chase day, perhaps the best one since last Wednesday. However, since the pattern looks to go down after that, I am likely to leave the Plains on Wednesday.

May 29: western Nebraska

2010-05-29T09:37:00.000-07:00

Despite SPC's low risk, the forecast soundings and hodographs look favorable for briefly rotating storms and, perhaps, for a window of about 2 hours, tornadic storms, in the region roughly where I76 and I80 merge in Nebraska. Thom has gone home, and I will be joined for the last several days by Cameron Redwine as a storm chase partner. My regular "second half" of the chase partner, Scott Landolt, is with VORTEX2 for the next three weeks.

May 28: eastern Wyoming/extreme western Nebraska Panhandle

2010-05-28T09:48:00.000-07:00

The most favorable area for rotating storms will be in North Dakota and adjacent portions of South Dakota. Since Thom leaves from Denver early tomorrow morning, and I pick up Cameron Redwine as a chase partner for my last several days,, and also will be joining Chuck and Vickie Doswell tomorrow for the pattern setting up in Nebraska.

This is a picture of one of the Doppler on Wheels (DOWS) scanning the Tribune, KS supercell the other day. You can see Scott Landolt on the far left, and John Monteverdi next to him.

May 27: eastern Wyoming

2010-05-28T09:46:00.000-07:00

This ended up being a down day. We thought there was a large chance for rotating storms in this area IF storms initiated. They never did.

We overnighted in Torrington, Wyoming. The picture at left shows one of the Doppler on Wheels (DOWS) from Vortex2. At far left is Scott Landolt and to his left Thom. I posted a similar picture with me in it in the next post.

May 26: Adjusted Target--eastern CO

2010-05-26T10:21:00.000-07:00

We decided to chase into Colorado today as a Denver Vorticity Convergence Zone is setting up. And, we did indeed run into a nice looking, sculpted supercell. For a brief moment in its lifecycle (~30 minutes) it spun up a wall cloud, and looked good on radar.

However, the low level rotation never tightened up. The wall cloud never looked like a tornado producer, although a few funnel clouds did develop (you can see one on the left, south side of the wall cloud in the picture below).

We followed the storm as it slowly propagated northeastward. While it was near Inerstate 76, its base shrunk, and we decided to call it a day.

We overnighted in Fort Collins.

May 25 Southeastern CO/OK Panhandle Addendum--Mammatus and One More Tornado Shot

2010-05-26T09:16:00.001-07:00

The first picture shows the main wall cloud getting wrapped in rain. This interferes with the tornado forming processes, but you can see what was left of tornado #7 for us on this day

The other shots are of the backside of the storm as it left our area. This is the best display of mammatus that Thom and I have ever witnessed. It's truly a Steven Spielberg special effect. Bh the way, we took many high resolution pictures, and have had time only to look at about half of them. Who knows what interesting features might emerge when we have time to look more closely at all of our photography and video.

May 25 Southeastern CO/OK Panhandle--Nine Tornadoes

2010-05-25T11:06:00.000-07:00

What a terrific day.

We really maximized our good forecast with equally good luck, running into a storm at the time it was producing multiple "landspout" (non-supercell) tornadoes, and then watched it produce three supercell tornadoes.

Finally, we were treated to an outstanding display of mammatus.

May 23: South-central South Dakota

2010-05-24T08:45:00.000-07:00

There is a volatile pattern setting up for fast moving supercells in South

Dakota, and perhaps northwest Nebraska. We are on the way....form Goodland.

Hodographs favor fast motions, but also a few tornadoes....with some strong and violent.There is a volatile pattern setting up for fast moving supercells in South

Dakota, and perhaps northwest Nebraska. We are on the way....form Goodland.

Hodographs favor fast motions, but also a few tornadoes....with some strong and violent....

....and we should have stuck with our target. But storms erupting ahead of the cold front in western Nebraska were supercells and were producing tornadoes early on. So we attempted to get along that line and wait for the rapidly moving storms to train up the boundary to us.

One in particular near Alliance (see radar) had a history of producing TVS (tornado vortex signatures) and was intermittently tornado warned by the NWS. However, by the time we got in position, the whole area erupted into a rapidly moving squall line. Outflows from neighboring storms crashed through our storm and it became non-supercellular and absorbed into the line.

If we had left at 7AM we may have made it to our target in time to see South Dakota tornadoes at 1PM. That's about 6 hours earlier than tornadoes normally form. But them's the breaks...

May 23: Northwest KS Tornado

2010-05-23T09:32:00.000-07:00

Thom and I, with Scott Landolt and Daniel Porter, dropped southwestward from O'Neill, Nebraska to the Oakley, KS area, and were rewarded with an active chase day, culminated by a narrow cone/snake tornado about 20 miles west of Oakley. This was associated with a really nicely structured supercell, that was one of a group of such storms that developed or evolved over northwest KS as the dew point surge at the surface advected under gradually more favorable deep layer shear during the day.

The day ended with all of us trying to get a view of the storm of the day, a cyclic tornadic supercell that nearly clobbered Goodland.

The "trying" part is a bit of a story, particularly for Thom and I. We missed the short cut to the 83 southbound exit in Oakley to get to the first storm, and then when we back tracked down 83 from I70, we missed the Highway 40 west bound that would take us to the storm. As a result, we were nearly late, and it did cost us good photography. However, we did see the tornado and its parent bulbous wall cloud. It was a relatively distant view, but it was beautiful and exciting.

Then, we tried to get north to I70 to perhaps stay with that storm, only to be stopped by a cross-highway accident. Thus, we had to backtrack to H40, then east to H83 before coming up to I70. And, thus, we missed an opportunity to see the wedge and cone tornadoes with the Goodland storm.

It was still a highly successful day....(there was another chase of another briefly supercellular storm before all of this)...and ended with Thom and I iin Goodland as a line of severe storms passed through, with 60-70 mph winds, knocking out power until around 10 minutes ago.

Tomorrow, Thom and I are off to Nebraska, to explore what might be yet another very productive weather pattern during this week.

May 22:Tornadic Supercell in North-central South Dakota

2010-05-22T14:04:00.000-07:00

We eventually ended up playing the dry line bulge in north-central South Dakota. We were rewarded with a series of amazing storms, and did make it to the area in time to catch up to a long-lived cyclic supercell, repetively producing tornadoes. We caught up to the storm in one of its last cycles before the whole area erupted into a line.

The storm had a monstrous hook and the picture shows a wedge tornado about 20 miles southwest of Aberdeen, South Dakota. As we dropped south away from this storm, in the dusk, we outraced the lowering and the shelf that hung out east-southeastward from it. We could see it hanging like the lip of a mother-ship spacecraft over the road to our west (right), with a suspicious underhang directly over us (which did not become a tornado).

We dropped south to O'Neill, Nebraska for the night.

May 21: Into Nebraska Panhandle

2010-05-22T11:55:00.000-07:00

Expecting storm formation on the Cheyenne Ridge and on the mountains, Thom and I hung around Goodland for a while, before we began drifting northeastward. Forecast storm motions would take such storms towards Goodland. But temperatures and dew points never reached their forecast values.

However, further north, storms forming on the eastern ranges of the Rockies began drifting out into the Plains north of the Cheyenne Ridge. So, after joining Scott Landolt near Scotts Bluff, we hung with a tornado warned storm moving into the Nebraska Panhandle. It briefly had a wall cloud, and looked good on radar, before it began to disorganize.

We overnighted in Chadron, Nebraska.

May 20: Moving towards northeast Kansas/ne Colorado

2010-05-20T09:46:00.000-07:00

I think that the upslope area of northeast CO/NW KS/sw Nebraska looks interesting tomorrow. We are in Dodge today and will reevaluate our destination for tonight based upon the 12 UTC run of the models. The huge discrepency betweem the SPC outlook for Saturday and the 0000 UTC NAM. The latter has a gigantic potential for north-central Nebraska, but SPC has the risk way up in the Dakotas.

Anyway, there will probably be some lightning photography opportunities this evening up in ne Colorado/nw KS, so we will probably head up that way today, and then the next two days look great.

Meanwhile, we upgraded from a full sized car to a mid size SUV. This drives great in the rain, and also gets reasonable gas mileage. Here's a picture of our Chase Vehicle, a Dodge Jericho mid-size SUV. Be sure to check out the other side of the story at Chasing Storks.

May 19: Arrival and Long Drive

2010-05-19T20:32:00.000-07:00

We changed our flight to a 6:25 Am departure (from 9:20 AM), to give us a shot at the terrific setup forecast for central Oklahoma. It was a long shot....we figured 590 miles to get to the Clinton-Taloga area, and then if and only if the storms did not fire early and stayed back west.

As it is, the storms DID fire early, and were along I35 before we got to the Oklahoma border about 150 miles west of that at around 7PM. Faced with still doing a "catch-up chase" (called "stern chase" by severe weather meteorologists) to storms moving away from us, we called it a day, and pulled back to overnight in Dodge City KS.

Turns out that there was enough vertical shear and low level instability to generate a class of storms called "low topped" supercells in western KS. We arrived in Dodge City to the sound of tornado sirens, and an interesting looking sky near sunset, with a low hanging base with inflow fingers. Too dark for pictures. Here's a radar plot.

2010 Chase Begins May 19

2010-05-10T10:43:00.000-07:00

Flying into Denver...

5/27/09: The Pattern and More

2009-05-27T09:24:00.000-07:00

I learned a valuable lesson the last few days of my trip (I am sitting here at DIA waiting for my plane as I type this). I realize that most severe storm researchers here are looking ahead to a possible pattern shift, and what's happened in Colorado the last few days may not seem important.

But that Commerce City storm three days ago, and the storm southwest of Limon were eye openers for me. Those were not "landspout" storms (in the sense of a non-supercell thunderstorm just spinning up vorticity of the boundary layer). These were storms that formed initially in an environment that should not have supported supercells in the sense of the deep layer shear. Yes, yes, we are all used to pontificating about storm motions off the hodgraph and how you can get supercells in otherwise unfavorable environments. We all use the term "mesoscale accidents" to refer to storms that become supercellular out here without the obvious shear signatures in the morning's hodographs and wind profiles.

But even though I know that, and all severe storms researchers know that, I doubt anyone chasing Colorado those the Denver Convergence and Vorticity Zone (DCVZ) days over the weekend were thinking "...oh, I really think some mesoscale accidents will happen and, forget single cells spinning up a spout, we are really going to see some good structure..." Maybe someone did. I didn't. All that I know who were out here were looking for landspouts, no more, no less.

Frankly, those two days felt like "chase" days to me in the traditional sense. Thom and Scott and I were chasing supercells, with the updrafts in the correct locations with respect to the forward flank, with RFDs, etc. You know what, those two days allow me to leave the Plains feeling as if this trip was somewhat successful. Scott and I may write up something on the DIA storm on 24 May because of this.

But there's something odd about this pattern that we are in. Perhaps it relates to global warming, perhaps not.

I think the consensus from the linked ocean-atmosphere models used to project climate trends into the late 21st century show that most of the "warming" will take place in the upper middle and polar latitudes. If that's the case, the meridional temperature gradient will decrease a bit at the same time that the mean temperatures of the whole shabang go up.

Decreasing the pole-equator temperature gradient USUALLY means higher wave numbers (more long wave meanders). This suggests that whatever controls external to the atmosphere are at play (say SST patterns) might act to anchor these meanders. Suppose one "anchor" was a trough on the West Coast....that had a response a ridge over the Plains downstream. Then we'd have a season or a period like the one we've just experienced.

Suppose another time the anchor was in a different location, so that a mean trough sets up over the Rockies. That's what I meant really. I am not trying to relate mean temperatures to lapse rates or anything like that.

All other things being equal, the latter would result in a "synoptically-evident" pattern for severe weather in the Plains. And that could go on for weeks, or even months.

As far as lapse rates go, if the heating is equally distributed through the troposphere's depth, then the environmental lapse rate won't change much. However, the higher mixing ratios mean that when storms do go they would go with more CAPE. Hence, maybe not more storms, but storms, when they occur, that would be more violent. Who knows about how the lapse rates will really be affected, though.

There is much to ponder here for severe storms meteorologists and climate change atmospheric scientists.

05/25/09: Carlsbad and Exit

2009-05-26T06:47:00.000-07:00

Last night Scott and I witnessed the bat flight from Carlsbad Caverns. Because of the dry conditions locally the usual number of bats had not been making this flight; there were not enough insects for them to forage. The previous night the rangers told us only 10 bats had come out. The usual size for the colony is 400,000 bats. When Thom and my nephew Bruce and I saw this event in the early 2000s, it was an awesome vortex of black rushing out of the natural opening of the cave.

Well, fortunately, last night a respectable bat flight did occur. Though smaller in size than I remember it, the flight still probably had 100,000 bats or so exiting over 15 minutes.

Today, we are leaving early to descent into the caverns for the two to three hour walk (goes about three miles). This will be my sixth time through, and I have yet to tire of this spectacular descent into a wonderland of colors, shapes, and spaces.

5/25/09: On to se New Mexico

2009-05-25T08:57:00.001-07:00

Our initial plan is to hope that the dry line does not set up too far east today. But, even if it is in southeastern New Mexico, where the shear environment appears somewhat favorable for a rotating storm or two, the moisture return from the Gulf is still meager. There is still a disjoint between where the greatest buoyancy is and the best shear. This has been showing up in the last few runs of the models.

We'll reevaluate as we travel. Meanwhile, we are planning to see Carlsbad Caverns...the bat flight tonight, and the caverns themselves tomorrow morning before all the tourists overun it.

Here's another picture of the fabulous rotating storm we witnessed yesterday.

5/24/09: Viva Las Vegas....

2009-05-24T19:52:00.001-07:00

...New Mexico, that is. Which is where Scott Landolt and I are overnighting. We left Thom off at Denver Airport but decided to stay in the area. A Denver Convergence Zone was developing again, basically a reprise of yesterday. And, this decision paid off for us all.

It turns out that we ended up chasing right to Denver Airport. Thom's flight was in the late afternoon, so while we were chasing and he was waiting, a supercell developed west of Denver Airport. The radar development was spectacular, and the storm ended up producing a marvelously wrapped wedding cake, corkscrew updraft area.

Yes, Thom was in the Airport when the tornado warning was issued, the sirens wailed, the klaxons sounded, and all were asked to the tornado shelters and planes were vectored off.

We are not sure if the storm produced a tornado. We did see two funnel clouds with earlier storms, and Cameron Redwine reported a funnel at the time of maximum development. I'll post more when I get my pictures downloaded.

5/23/09-Part B: Denver Cyclone Produces

2009-05-23T19:43:00.000-07:00

Well, on Thom's last day, we actually had a traditional chase.

We dropped down to the Palmer Divide by early afternoon. There seemed to be a boundary with ESE flow south of the Divide and northwesterly or northeasterly winds north of the divide. Low to mid 50 dewpoints abounded.

When we got to Limon, a strong set of echoes was between Colorado Springs and Limon. Just after our arrival there, the northern most of the echoes developed a rain free base, and then, somewhat to my amazement, a fairly good looking wall cloud. We dropped south and noticed that at least at the base of the wall cloud there was decent, but not strong, cyclonic motion.

As the storm moved over us, the wall cloud became outflowish, but left behind on its eastern periphery was the high based funnel, nearly tilted horizontally. All in all, this was a very satisfying chase day. We salvaged an actual chase out of this wreck of a pattern. It also goes to show that what meteorologists call "mesoscale"accidents can produce bounty. A "mesoscale accident" is something that cannot be assessed by looking at computerized weather forecasts, but changes conditions favorable to those for rotating storms by some local effects that are difficult to assess, if not impossible (topography, boundaries from neighboring thunderstorms etc.) True, we did not see a tornado. But others reported brief tornadoes. Our high-based funnel is consistent with those reports.

5/23/09: Denver Cyclone Reprise

2009-05-23T09:41:00.000-07:00

The morning's surface weather maps shows, basically, a reprise of yesterday's pattern. A subsynoptic low is centered northeast of Denver, and, for this portion of the Plains, a rich supply of moisture is evident (basically, dew points in the mid 50s at 4000-5000 feet corresponds to dewpoints in the low 60s at sea level).

For Thom's last "chase" day, we will be playing the Palmer Divide, east of Denver. This is the sort of pattern in which strong, early updrafts can spawn a non-supercell tornado (called, popularly, "landspouts"). Here's a picture of the two of us at Mt. Rushmore.

This has been an uneventful trip so far (and likely to end so for me too). However, our frustration is tempered by the successful trips we had in 2004 and earlier years. This year's pattern is particularly frustrating for the participants of the VORTEX2 experiment.

This huge operation, involving over 40 vehicles stationed at three locations over the Great Plains, and deployed to observe the microscale meteorology around tornadic storms, has been deployed exactly once since the operation started on May 10. That was this past Tuesday, when we saw a few supercells in the Nebraska Panhandle. However, these were not close to being tornadic.

Thunderstorms are likely to occur over this region (as they have occurred the last few days) over the next weeks or so, but projected shear patterns do not indicate that they will be tornadic. Hence, many chasers are making the decision to abandon their quests this year...the mission is not to find thunderstorms (which is an easy thing to do) but to find rotating thunderstorms (which is a much more challenging proposition).

5/22/09--Part 2: Storms in NE Colorado

2009-05-22T19:30:00.001-07:00

A Denver Convergence Zone developed in the late afternoon. This took the high dew point air previously described in a counterclockwise spiral around Denver International Airport, with some strong storms developing.

We were hoping for a non-supercell tornado (very common with this type of pattern) but, alas, although we had some fun chasing a strong storm (see right) near Akron, the whole area eventually erupted in moderate and heavy rain.

The picture was shot from the location, basically, shown on the radar plot. The yellow circles indicate our GPS position.

5/22/09: Northeast Colorado/Southern Nebraska Panhandle

2009-05-22T09:34:00.000-07:00

Very sluggish flow in the midlevels today....but if the 20 knots of southwesterly flow at 500 mb verifies, surmounting 15 knots of southeasterly flow, there are adequate dewpoints and moderate CAPE in northeast Colorado and southern Nebraska Panhandle today. Adequate for briefly rotating thunderstorms...

...of course, there has to be thunderstorm initiation, which did NOT occur yesterday. We overnighted in Garden City, KS, and we both got good workouts in....Thom running 10 miles on a bike trail here, and me 4 miles or so, plus a good long weight workout at the YMCA. It is now 11:30AM and we are now about to depart.

05/21/09: To the Good Land (that is, Goodland, KS)

2009-05-21T10:14:00.000-07:00

Today's pattern suggests a bit of a focus for rotating storms in northwest KS today, but the "ifs" are really problematic. The mid-tropospheric winds have weakened, but the surface easterly flow should yield reasonable vertical shear values....however, not quite phased with the highest dew points (about 30 miles out of phase). Nevertheless, we are here to chase potential storms, so we will shortly drop south from Ogalalla, Nebraska into that area.

Yesterday, the marginal moisture at lowest levels had the effect we expected. We did indeed get rotating storms....two supercells that we witnessed, albeit with high bases. The cloud base rotation was quite evident in the swirls where theupdraft was centered. We also saw VORTEX2's armada....over 40 vehicles...quite impressive.

The upcoming pattern does not look good for storm researchers. I am liable to leave the Plains earlier than I have ever in previous chase years. Thom is leaving on Sunday, and Scott and I are liable to try one last play in Texas early next week

See more pictures.

5/20/09: Target-Northeastern Nebraska Panhandle

2009-05-20T09:44:00.000-07:00

Post frontal upslope flow along and just south of the South Dakota border should bring some marginal dew points into that area this afternoon. The environment is developing a shear profile very favorable for supercells in that area too. The large dew point depressions are liable to produce high lifting condensation levels, though, and the storms are likely to have high bases.

There is a tug of war between the RUC and the WRF models today, with the WRF having higher dew points spread over a larger areas,

and moderate to high values of CAPE (s

ee forecast Valentine sounding). Right now it appears that we will see an LP supercell today...but there is always the hope of a "mesoscale" accident producing a supercell tornado, as Thom and I saw near Miami, TX in 1994. Non-supercell tornadoes are very possible today, and we'll take one of those.

Yesterday we visited Mt. Rushmore. This was the first time I have seen Rushmore, and I have to say it is impressive. On our way south today we may stop in at Wind Cave National Park.

5/19/09: Rapid City to extreme eastern Montana

2009-05-19T10:09:00.000-07:00

Both the RUC and the WRF persist in bringing relatively high dew points into a modestly good shear environment (see forecast sounding/hodograph for Rapid City this afternoon--favorable for rotating storms that will persist for a short while until the precip plume overwhelms the updraft). Hence, we are going to hang around the Black Hills and areas north today (perhaps taking in Mt. Rushmore).

Today I have included a picture of our chase vehicle, the Jeep Commander that Thom has told you about in Wild Geese. It's actually a good vehicle. Plenty of room, and it gets around 20 mpg. The rear panel folds up and provides protection from rain, and there is a wide bench to hold our cameras back there.

5/18/09: Off to Rapid City

2009-05-18T10:28:00.000-07:00

The basic prognosis remains the same. The wind profiles look marginal to good for the region initially just north of Rapid City, SD (Tuesday), the Nebraska Panhandle into SW SD (Wednesday) and nw KS to sw Nebraska (Thursday).

However, the moisture profiles look poor to marginal initially, to marginal by Thursday. Dew points are expected in the 50s to upper 50s in this region (see graphic for Tuesday).

So, we are on our way north to Rapid City, SD today. With the shear profiles during the period, isolated storms are liable to rotate briefly before being enswirled by their own precipitation plumes.

But, at least there is a risk for rotating storms.

5/17/09: May 20th (Possibly the 19th) Looks Like First Day

2009-05-17T09:04:00.000-07:00

The WRF-NAM is now in range of the early period, and still corroborates that there might be just enough low level moisture for storms to develop in an environment with a looped hodograph, albeit short (~35 knots of shear) over northern third of Nebraska, eastern Wyoming, and southern South Dakota on Tuesday (19th), with similar to better conditions the next two days..

So this appears to be our last "relax" day. (Last night we saw the movie "Angels and Demons.")

Then the surface pattern slowly evolves southward, with slightly better dew points as air comes around the horn, and the pressure pattern redistributes higher dew points over the southeast, leading to non-tranditional trajectories. So by Thursday or Friday we will be in north central KS or southwest Nebraska.

By the way, I have had complete agreement with whomever has been writing the 4-8 Day thunderstorm outlook for SPC, who also has highlighted the fact that the pattern could generate severe/rotating thunderstorms in the Tuesday-Thursday period. One of those forecasters also mentioned high based supercells, but all concluded the overall risk is too small to include in a 30% outlook at this time. That's exactly the way we feel.

We may be looking at blue sky, but we also might have rotating storms.

See The Rest of the Story

5/16/09: Same issues/Same Target

2009-05-16T09:14:00.000-07:00

We are in Denver, and plan to overnight in Boulder. The latest run of the medium range models still suggest that both deep layer and low level shear will be adequate for severe storms/supercells during the Tuesday-Thursday period in the region about 150 miles radius from Rapid City, South Dakota.

The largest issue remains the circulation in the Gulf of Mexico, which is taking Gulf air southeastward into a developing tropical system. Nevertheless, either locally produced, or imported moisture does make it northward through the Tuesday-Thursday period. I have posted the dew point field forecast for Wednesday afternoon. It does represent the most robust dew point field of the week, and it does suggest some hope for storms, possibly supercells, in the region of favorable shear.

Dew points would need to be higher in order for LCLs to be low enough to get tornadic storms, however, even if the dew point field verifies.

5/15/09: Pattern Becomes More Murky

2009-05-15T15:50:00.000-07:00

The models are still advertising two of the three ingredients in supercell production to be in place in the northern Plains starting about Monday or Tuesday. The one "missing" ingredient is boundary layer moisture.....which would appear with southerly or southeasterly flow at the surface usually....but NOT if the big cyclone development occurs down in the Gulf of Mexico.

The models "think" that a hurricane may form that way, which may actually take moisture headed for the northern Plains and shunt it southward into the circulation. We shall see...although it looks like that will occur.

Meanwhile, there still will be storms in the Dakotas, perhaps northwest Nebraska and eastern Wyoming and Montana starting around Monday, perhaps Tuesday, and that is we are likely to head after landing in Colorado and spending a day or so in Boulder.

5/14/09: GFS Continues To Point to Northern/Central Plains

2009-05-14T11:39:00.000-07:00

I've attached the 500 mb, surface pressure, and surface dew point forecasts for next Tuesday, which is similar, with slight modifications, to those for next Wednesday and Thursday afternoons. If the pattern verifies, we will be drifting northward from Boulder on Sunday to South Dakota.

The focus appears to be setting up for some place with a radius of 150 miles of Rapid City or so. That's conditioned on the model being correct, of course. The pattern is somewhat favorable, but highly contingent on dew points rising into the mid 50s to get high-based supercells. We'd really need much higher surface dew points to see more dramatic storms. But at least there is some possiblity for T-Th

The Ensembles still show a majority of members favoring the progression of a trough into the West Coast after Saturday. So that's our plan now.

5/9/09 European Model Ensembles On-board

2009-05-09T12:22:00.001-07:00

This is today's run of the ECMWF's ensembles. It's valid for Sunday, 17 May, and shows basically what the GFS has been showing....most of the ensemble members have a sharp shortwave trough in the southern branch just entering the central and northern Plains on Saturday night to Sunday morning.

If this trend continues, this will be yet another validation of our decision in the early 2000s to make our entrance airport Denver's.

5/7/09: Ensembles Suggest Central Plains for Our First Days

2009-05-07T20:50:00.000-07:00

Just a heads up...the GFS ensembles are suggesting a favorable pattern in the central Great Plains for the first few days of our trip.

Where Are We?

2009-05-06T08:45:00.000-07:00

A spiffy new widget will now allow viewers to see exactly where we are along with any storms in the area. Just click on the link at the top right of this page, or go to our website at http://www.tornadochase.org/.

2009 Chase Photos

2009-05-01T11:07:00.000-07:00

To view our photos for the 2009 Chase (May 16-June 1) click on the link at the top right of this blog. 2009 Storm Chase Photos

Departure Date - May 15

2009-05-01T10:32:00.000-07:00

We are heading off to Denver on Friday May 15 to begin the 2009 chase season. Late arrival and overnight near airport. 5K fun run the next AM, then off to the chase!

Testing of New Blog

2009-04-29T22:51:00.000-07:00

This is the first post for TornadoChase.org blogsite. This post includes a photo uploaded from the computer and shown as a large thumbnail on the left. If you click on the photo you will see the full-size version.

Photos can be located on the right, left or top of the text.

Video clips can also be inserted.