U.S. Severe Weather Forecast (Convective Outlook)

Day Three

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Storm Prediction Center ac 200819 

Day 3 convective outlook 
National Weather Service Storm Prediction Center Norman OK 
0219 am CST Tue Nov 20 2018 

Valid 221200z - 231200z 

..no thunderstorm areas forecast... 

severe thunderstorms are not expected on Thursday. 

..synopsis and discussion... 
A progressive shortwave trough is expected to move eastward from its 
early period position over the western Great Basin to the 
central/Southern Plains by 12z Friday. Lee cyclogenesis is 
anticipated ahead of this shortwave across the Central High plains, 
with the resulting surface low likely located near the western Kansas/OK 
by the end of the period. Enhanced surface pressure gradient between 
this low and its associated troughing across the plains and high 
pressure over the northeast will result in southerly wind across the 
Southern Plains throughout much the period. Even so, winds across 
the Gulf will remain predominately easterly until after 00z Friday, 
limiting moisture return and keeping the air mass stable. 
Consequently, thunderstorm development is not anticipated during the 
period across the Southern Plains. 

The best chance for thunderstorms appears to be off of the northeast 
Florida/southeast Georgia coast where a low-amplitude shortwave will interact 
with moist and marginally unstable air mass. Highest coverage will 
be offshore with inland areas having thunderstorm probabilities of 
less than 10%. 

.Mosier.. 11/20/2018