SPC 0700Z Day 2 Outlook

Day 2 Outlook Image

Day 2 Convective Outlook  
NWS Storm Prediction Center Norman OK
1256 AM CST Wed Nov 25 2020

Valid 261200Z - 271200Z


Isolated large hail may occur with thunderstorms that develop across
parts of east Texas and Louisiana, mainly from Thursday night into
early Friday morning.

...Coastal/East Texas into Louisiana...
A positively tilted upper trough is forecast to move southeastward
over the western/central CONUS, with the southern portion of this
system closing off over the Southwest late Thursday. Ahead of this
feature, low-level moisture return should occur across parts of
coastal/east TX and the lower MS Valley through the period. 700-500
mb lapse rates around 7-7.5 C/km emanating from the higher terrain
of west TX and northern Mexico may overspread this region late
Thursday into early Friday morning. Latest guidance suggests MUCAPE
around 1000-1500 J/kg may develop along/north of a warm front, with
strengthening west-southwesterly mid/upper-level flow with height
that should support 40-50 kt of deep-layer shear. Confidence has
increased that mainly elevated storms may form by late Thursday
evening in a modestly strengthening low-level warm advection regime
over parts of east TX into LA, generally to the north of the warm
front. The forecast combination of sufficient instability, steep
mid-level lapse rates, and strong speed shear in the mid/upper
levels suggest that isolated large hail may occur with any elevated
supercells that can develop. The potential for surface-based storms
along the immediate upper TX Coast and southwestern LA remains too
uncertain to include any probabilities for strong/gusty winds at
this time.

...East Coast...
A de-amplifying shortwave trough should move across the Mid-Atlantic
and southern New England on Thursday. A weak surface low associated
with this feature is forecast to fill further through the day. An
eastward-moving cold front should extend from the Mid-Atlantic
southwestward along parts of the East Coast and into the Southeast.
The stronger mid-level flow attendant to the shortwave trough should
remain displaced to the north of greater low-level moisture across
the Carolinas and Southeast. Although enough weak instability may
develop across eastern portions of the Mid-Atlantic and southern New
England to support isolated thunderstorms Thursday afternoon, truly
surface-based convection still appears unlikely. From the Carolinas
into the Southeast, additional storms may occur through the day
along/ahead of the cold front. These areas will remain generally to
the south of stronger forcing for ascent tied to the previously
mentioned shortwave trough, with overall storm coverage expected to
remain fairly low.

..Gleason.. 11/25/2020

Read more
There’s more click here.

Comments are closed.