May 20, 2009

5/20/09: Target-Northeastern Nebraska Panhandle

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.