3/7/06 FCST: Central / Southern Plains

[Glen Romine]

Originally posted by Bill Tabor
Well, I will also note that SPC mesoanalysis also shows a small area of -50 cinh in south central OK.

I don't think that will help much based on use of the same product suite. If you look at the LFC - it's up around 3 km - and the LCL - LFC height difference is ~ 2km - no thermal is going to get air that high today no matter how sunny. Assuming these products aren;t out to lunch, since there doesn't appear to be any substantial boundaries to force ascent that high - the prospects for initiation even with a CINH of 0 are not good. If anything, the dewpoints across southern OK have been slowly falling as peak heating (and peak mixing depth) has arrived. Further north, there have been pressure falls associated with upper level divergence across nw OK, but the moisture quality is poor there, cloud cover is thickening and convergence is not very impressive. Stranger things have happened - but I put the prospects of surface based convective development down to about 10% now. Think we will need to see the BL decouple before storms will develop, and the signs for an MCS developing are looking weaker in the more recent RUC runs - if nothing else the next shortwave looks too far west relative to the morning NAM forecast position - so that may arrive closer to 6-9Z.

Glen

 

[Bill Tabor]

Originally posted by Glen Romine+--><div class='quotetop'>QUOTE(Glen Romine)</div>

<!--QuoteBegin-Bill Tabor

Well, I will also note that SPC mesoanalysis also shows a small area of -50 cinh in south central OK.

I don't think that will help much based on use of the same product suite. If you look at the LFC - it's up around 3 km - and the LCL - LFC height difference is ~ 2km - no thermal is going to get air that high today no matter how sunny. Assuming these products aren;t out to lunch, since there doesn't appear to be any substantial boundaries to force ascent that high - the prospects for initiation even with a CINH of 0 are not good. If anything, the dewpoints across southern OK have been slowly falling as peak heating (and peak mixing depth) has arrived. Further north, there have been pressure falls associated with upper level divergence across nw OK, but the moisture quality is poor there, cloud cover is thickening and convergence is not very impressive. Stranger things have happened - but I put the prospects of surface based convective development down to about 10% now. Think we will need to see the BL decouple before storms will develop, and the signs for an MCS developing are looking weaker in the more recent RUC runs - if nothing else the next shortwave looks too far west relative to the morning NAM forecast position - so that may arrive closer to 6-9Z.

Glen[/b]

Yep, good points. I tend to agree. It's gonna be tough.

 

[Chris Allington]

looking at TWX's last couple of frames it appears that some weak convection has initiated at is moving rapidly east, as the short term forecast states, 55mph. So far it appears that nothing is really happening with these storms but if they intensify we could have the potential for some hail... i dont think that storms will initiate before sunset in OK. With capping, and upper level support behind where is was forecast to be it would take a pretty decent localized area of convergence to do something... but we can all hope right? Anyway i think it will mostly be elevated hailers after dark...

 

[John MacKay]

SPC issued two MDs for WWs (severe), one in SC-SE KS and one across much of northern MO. The one in KS mentions initiation on ICT or to the south/east of ICT.