Severe Storm Outlook Narrative (AC)
Issued by NWS

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35
000
ACUS01 KWNS 150533
SWODY1
SPC AC 150532

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1232 AM CDT Fri Mar 15 2024

Valid 151200Z - 161200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
SOUTH-CENTRAL TEXAS AND THE MISSISSIPPI/ALABAMA REGION...

...SUMMARY...
Scattered strong to severe thunderstorms are possible across
portions of south-central Texas and over parts of
Mississippi/Alabama region.

...South-central TX...

Confluent high-level flow over the middle of the CONUS will
encourage surface anticyclone to settle south across the Plains
today, though some weakening is expected across the southern Plains
late in the period. Latest water-vapor imagery suggests a weak
midlevel short-wave trough is approaching south TX early this
morning. This feature is forecast to advance into the lower MS by
18z as associated 500mb speed max translates downstream into the
central Gulf States. As a result, neutral-weak height rises are
expected across south-central TX by afternoon.

As this low-latitude short wave approaches higher-quality moisture,
there is some concern that early-day elevated convection may
develop. Several HREF members suggest isolated supercells initiate
ahead of this feature. However, forecast soundings are quite capped
so any activity should remain isolated.

Of more concern is the strong surface heating anticipated across
northeast Mexico into portions of south TX ahead of the synoptic
front. Forecast soundings ahead of the boundary suggest convective
temperatures will be breached as readings warm into the lower 80s.
NAM sounding for DRT at 22z exhibits negligible CINH with SBCAPE on
the order of 2500 J/kg with a temp/dew point of 83/62F. Strong
surface-6km bulk shear and weak frontal convergence favor
thunderstorm development and supercells appear possible. Large hail,
some of it potentially bigger than 2 inches, is the primary risk
with these storms. While convection should initiate due to strong
heating, thunderstorms will likely linger well into the overnight
hours as an increase in the LLJ is expected during the latter half
of the period into this portion of TX.

...MS/AL...

Southern-stream short-wave trough will approach the lower MS Valley
around 18z before advancing into the southern Appalachian region by
16/00z. In response to this feature, LLJ will be focused across
MS/AL early, then veer into the west across GA as the short wave
progresses downstream. Synoptic front will likely prove instrumental
in convective development as it advances slowly southeast across the
Gulf States. Forecast profiles suggest organized convection is
possible, with some risk for supercells given the strong shear and
modest buoyancy. While low-level SRH is not particularly strong, a
tornado or two can not be ruled out with this activity, though
damaging winds may be the greatest risk.

..Darrow/Wendt.. 03/15/2024

$$


USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.