9/14/05 FCST: Southern Plains

[Bill Tabor]

One big concern for me - not mentioning other things is the negative PVA values for Tx and OK this afternoon:

http://www.rap.ucar.edu/weather/model/eta0...6hr_500_vrt.gif
http://www.rap.ucar.edu/weather/model/eta1...2hr_500_vrt.gif

This should contribute to subsidence.

 

[nickgrillo]

SDS forecast sounding (at 21Z) shows a SFC parcel of 92F/70F - yielding 4366j/kg of CAPE. Very strong and distinct veering is present from the 500MB to the surface layer... Which is yielding strong deeplayer shear in excess of 40-50kts across the threat area. Additionally, an OFB draped across western OK into NW TX will enhance low-level shear and moisture pooling, bringing a stronger risk for tornadoes. As noted by Jeff, rather weak flow in the from the 0-3km layer will be compensated by extremely strong directional shear in the same layer - with georgous veering profiles from westerlies at 500MB to backing SE winds at the surface.

I'm in a huge rush today... But I'll try to check back a little later.

 

[Mickey Ptak]

Moved from Now thread:

Looks to be I meso low close to Tillman and Jackson Co in Ok attm
http://weather.cod.edu/wx/public/sfc/states/ok.sfc.gif
http://www.spc.noaa.gov/exper/mesoanalysis/s1/mcon.gif

Plus a cu field has be developing in this same area for that pas hour or so.
http://weather.cod.edu/satellite/1km/N_Texas.gif

There is also that OFB that Bill has posted south of that area and Convective temps are forecasted to be 90deg and from the surface obs it seems that that will not be a problem in the cleared areas.

Mick