SPC AC 040741
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0141 AM CST Fri Dec 04 2020
Valid 061200Z - 071200Z
...NO SEVERE THUNDERSTORM AREAS FORECAST...
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.
NOTE: THE NEXT DAY 3 OUTLOOK IS SCHEDULED BY 0830Z