Dec 4, 2020 0830 UTC Day 3 Severe Thunderstorm Outlook
Updated: Fri Dec 4 07:41:36 UTC 2020 (20201204 0830Z Day 3 shapefile | 20201204 0830Z Day 3 KML)
Probabilistic to Categorical Outlook Conversion Table
Categorical Graphic
0830 UTC Day 3 Outlook Graphic
Day 3 Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
No Risk Areas Forecast
Probabilistic Graphic
20201204 0830 UTC Day Probabilitic Graphic
Probability of severe weather within 25 miles of a point.
Hatched Area: 10% or greater probability of significant severe within 25 miles of a point.
Day 3 Prob. Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
No Risk Areas Forecast
   SPC AC 040741

   Day 3 Convective Outlook  
   NWS Storm Prediction Center Norman OK
   0141 AM CST Fri Dec 04 2020

   Valid 061200Z - 071200Z


   Isolated thunderstorms are possible across southern Florida Sunday
   night into early Monday morning.


   An upper level low over OK/TX on Sunday morning is forecast to shift
   eastward across the lower MS Valley while merging with an upper
   trough over the Midwest late in the period. A weak surface low and
   cold front will track eastward across the Gulf of Mexico well south
   of the northern Gulf Coast. However, strong southwesterly deep layer
   flow associate with the upper low/trough will result in strong
   midlevel warm advection and widespread showers are expected along
   much of the northern Gulf Coast. Thunderstorms are not expected with
   this activity given limited low level moisture and weak instability.
   Further east and ahead of the surface low/cold front, deeper
   boundary layer moisture will reside across the southern FL peninsula
   and increase during the overnight hours as southerly low level flow
   strengthens. While instability will be weak and midlevel lapse rates
   poor, a few pre-frontal thunderstorms appear possible during the
   overnight hours as shear and forcing increases. The poor
   thermodynamic environment should preclude any severe threat.

   ..Leitman.. 12/04/2020