U.S. Severe Weather Forecast (Convective Outlook)

Day Three

acus02 kwns 211715 
Storm Prediction Center ac 211714 

Day 2 convective outlook 
National Weather Service Storm Prediction Center Norman OK 
1214 PM CDT Tuesday Oct 21 2014 

Valid 221200z - 231200z 

..no severe thunderstorm areas forecast... 

isolated thunderstorms are forecast across the upper Mississippi 
Valley...middle Missouri River valley...Central Plains and southward 
into the southern High Plains and Rio Grande Valley Wednesday. A few 
storms will also be possible over southern Florida...the middle 
Atlantic coast into coastal New England and a small part of the 
Pacific northwest. 


Eastern U.S. Upper trough will evolve into a closed low and stall off 
the middle Atlantic coast. Meanwhile...upper trough currently moving 
through the northern and central rockies will phase with a weak southern stream 
trough and continue through the plains Wednesday...reaching the MS 
valley area later Wednesday night. 

The northern stream trough will be accompanied by a cold front that will 
advance through the northern and Central Plains...reaching the upper MS 
valley region Wednesday night. An occluded surface low expected to be 
just off the middle-Atlantic Seaboard Wednesday morning will develop 
northward during the day. 

..plains through upper MS valley... 

Owing to offshore near surface winds over the Gulf...instability will 
remain limited over the plains and MS valley. Nevertheless...at 
least weak MUCAPE /200-400 j/kg/ will exist ahead of the upper 
trough within plume of 6.5-7 c/km middle-level lapse rates and modest 
moisture being drawn northeastward above the surface layer. Scattered showers and 
isolated thunderstorms will likely develop over the plains as zone 
of deeper ascent shifts east...reaching the upper MS valley 
Wednesday afternoon and evening. 


A few showers and isolated thunderstorms will be possible in 
vicinity of a weak front over southern Florida...in association with closed 
upper low along the middle-Atlantic and southern New England coasts as well 
as over coastal Washington state. 

.Dial.. 10/21/2014