U.S. Severe Weather Forecast (Convective Outlook)

Day Three

acus02 kwns 211711 
Storm Prediction Center ac 211711 

Day 2 convective outlook 
National Weather Service Storm Prediction Center Norman OK 
1111 am CST Thu Nov 21 2019 

Valid 221200z - 231200z 

..there is a marginal risk of severe thunderstorms across parts of 
southeast Texas into la... 

Thunderstorms are expected from the Southern Plains into the lower 
Mississippi Valley Friday. A low probability of locally strong wind 
gusts and perhaps a brief tornado will exist from southeast Texas 
into Louisiana during the day. 

..southeast Texas into Louisiana... 

Showers and thunderstorms will likely be ongoing Friday morning 
along and ahead of a surface cold front. This cold front will 
stretch from southwest Arkansas into central Texas at the beginning of the 
period, shifting east/southeast from western la to the Texas Gulf Coast 
by 00z. Southerly low level flow ahead of the front will maintain 
surface dewpoints in the mid 60s to near 70 f. Cloudiness and shower 
activity will limit destabilization, with a narrow corridor of 
MLCAPE generally less than 1000 j/kg expected across southeast Texas 
into la during the late morning into the afternoon. Lapse rates also 
will remain poor, further limiting storm intensity. 

However, strong deep layer southwesterly shear will overspread the 
region as a shortwave trough shifts from the central/Southern Plains 
to the mid-MS valley. Effective shear near 40-50 kt will support 
some organized/rotating storm structures. Furthermore, while low 
level speed shear is not particularly strong, forecast soundings 
indicate small, curved hodographs ahead of the front near the Sabine 
River. As a result, an isolated strong to severe storms capable of 
locally strong wind gusts and perhaps a tornado will be possible. 

..maximum risk by hazard... 
Tornado: 2% - marginal 
wind: 5% - marginal 
hail: <5% - none 

.Leitman.. 11/21/2019