SPC 0830Z Day 3 Outlook

Day 3 Convective Outlook  
NWS Storm Prediction Center Norman OK
1225 AM CST Mon Jan 04 2021

Valid 061200Z - 071200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
Scattered thunderstorms are possible Wednesday afternoon and night
from eastern Texas into Louisiana and southwest Mississippi. A few
stronger storms are possible over southeast Texas during the
afternoon.

...Synopsis and Discussion...
On Wednesday, a positive-tilt upper trough will be situated over the
central and southern Plains, and will move eastward toward the lower
MS Valley by 12Z Thursday, providing large-scale lift. At the
surface, a ridge of high pressure will stretch from the OH Valley to
the central Gulf Coast Wednesday morning, and will move slowly
eastward with time.

A cold front will precede the southern Plains upper trough, with
weak low pressure forming from eastern TX into LA and MS. Primarily
mid 50s F boundary-layer dewpoints are expected ahead of this front,
with low 60s F along the TX and LA coasts leading to a few hundred
J/kg SBCAPE. Farther inland, elevated instability is also expected
to develop with MUCAPE of 100-250 J/kg, mainly north of the cold
front.

The most favorable combination of SBCAPE and shear will develop over
parts of southeast Texas during the afternoon. Here, winds will veer
with height, with 200-300 m2/s2 effective SRH developing, which may
support isolated severe storms. The cold front will be the primary
forcing mechanism, and will likely undercut developing storms. Given
this, and uncertainties regarding boundary-layer moisture quality,
will maintain sub-severe probabilities.

..Jewell.. 01/04/2021

Read more
There’s more click here.