NOAA Storm Prediction Center

Convective Outlooks

Convective Outlooks
The convective outlooks serve as guidance to the local NWS forecast offices and are used by emergency managers, private sector meteorologists, media, and other weather customers concerned with public safety. Three separate risk areas (slight, moderate, and high) are used to describe the expected coverage and intensity for the categorical severe weather threat on days 1-3 along with severe weather probabilities for the potential threat.

Day 1 Outlook Day 2 Outlook Day 3 Outlook Days 4-8 Outlook

Day 1 Outlook Convective Tornado
Hail Wind
Categorical Day1 1200Z Outlook
Images courtesy of the NWS Storm Prediction Center
 Forecast Discussion

ACUS01 KWNS 240544
SPC AC 240543

Day 1 Convective Outlook  
NWS Storm Prediction Center Norman OK
1243 AM CDT Wed Apr 24 2019

Valid 241200Z - 251200Z


Thunderstorms associated with large hail, wind damage and a tornado
threat are expected to develop across parts of south-central and
southeast Texas today and into western Louisiana tonight.

...TX and LA...
Showers and thunderstorms will likely be ongoing this morning from
portions of the middle Rio Grande Valley northeast into northeast TX
and behind a composite front/outflow.  Although an isolated strong
to locally severe storm is possible during the morning, it appears
the severe risk will focus over south-central TX beginning during
the afternoon.  Diurnal heating coupled with moist
south-southeasterly low-level flow will contribute to moderate
buoyancy by mid afternoon.  As the mid-level low over southwest TX
moves into central TX by nightfall, a belt of strong 50-60 kt
southwesterly 500mb flow will overspread the destabilizing warm
sector.  Supercells with an associated risk for large hail, severe
gusts, and a tornado are possible given the ample buoyancy/shear
profile---especially during the afternoon and early evening.  Models
suggest the orientation of the southward sagging boundary will favor
a transition to upscale growth as additional storm
development/mergers occur.  A couple of tornadoes embedded in the
squall line are not out of the question as the convective line
matures during the evening and moves from near/east of I-35 through
southeast TX into southwest LA.  It is within this west-east
corridor severe gusts may become more widespread as stronger
700-500mb flow becomes juxtaposed with a 40-kt southerly LLJ,
near/southeast of a weak surface low developing northeast from the
Hill Country into northeast TX.  The projected timing of the wind
threat begins in the late afternoon, shifting east during the
evening across southeast TX, and likely persisting into the
overnight into LA.  It is possible a higher probability tier of
severe wind probabilities may be needed but will defer to later

..Smith/Karstens.. 04/24/2019