U.S. Severe Weather Forecast (Convective Outlook)

Day Three

acus03 kwns 230635 
Storm Prediction Center ac 230634 

Day 3 convective outlook 
National Weather Service Storm Prediction Center Norman OK 
0134 am CDT Wednesday Apr 23 2014 

Valid 251200z - 261200z 

..no severe thunderstorm areas forecast... 

isolated strong...or perhaps one or two severe thunderstorms...may 
develop across parts of the southeastern U.S. And along a dryline 
over northwestern Texas and western Oklahoma. 

..sern u... 

Subtle but potentially significant short-wave trough will shift east 
of the Appalachians Friday afternoon. Timing of this feature does 
not correlate well with diurnal heating but it may prove adequate in 
generating a few thunderstorms across coastal Carolinas. If timing 
of short wave is too early then strong boundary layer heating could 
steepen low level lapse rates enough for a few Post-short wave thunderstorms 
within veered but modestly unstable airmass. For now will introduce 
5 percent severe probs to account for poor timing of short wave and 
weakly convergent low levels. 

..srn plains dryline... 

Lee trough/dryline is expected to begin sharpening across the southern 
High Plains Friday afteroon as troughing establishes itself over the 
western U.S. Intense boundary layer heating is forecast across western 
Texas/OK during the day where surface temperatures should soar through the 
80s to perhaps near 90f and this should be adequate in removing 
early-day inhibition. One major concern for organized deep 
convection along the dryline is the expected short-wave ridging 
forecast across this region during the afternoon. It/S not entirely 
clear how much convection will ultimately evolve...with the primary 
threat during the 22z-03z time frame. NAM is most aggressive in 
allowing a few high-based thunderstorms to evolve within airmass 
characterized by 1500 j/kg SBCAPE but strongly sheared...sfc-6km 
values approaching 50kt. Low severe probs have been introduced for 
isolated supercells that could produce large hail/wind. 

.Darrow.. 04/23/2014