May 18, 2011

First Day Target --- More or Less Unchanged

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.