SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1259 AM CDT Mon May 05 2025
Valid 061200Z - 071200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM CENTRAL TEXAS
INTO THE SABINE VALLEY...
...SUMMARY...
Severe thunderstorms are possible from portions of the southern
Plains into the lower Mississippi Valley on Tuesday. Severe winds,
large to very large hail, and a few tornadoes are possible.
Additional isolated strong to severe storms capable of large hail
and isolated wind damage are possible within parts of the northern
Mid-Atlantic states.
...Synopsis...
With the blocking pattern still in place, the upper lows in the Ohio
Valley and Southwest will continue to make slow progress on Tuesday.
A shortwave trough on the base of the upper low is expected to eject
into the southern Plains. This will promote severe potential across
much of the region into the Lower Mississippi Valley. Rich moisture
will continue to push into much of Texas and a warm front will lift
to near the Red River.
...Central/East Texas into Western Louisiana...
A complicated forecast exists across these regions. Convection is
anticipated to develop in West Texas along a retreating dryline late
on Day 1/Monday. Models are in general agreement that some of this
activity will persist into Tuesday morning in central Texas. A very
moist airmass (mid 60s to low 70s F dewpoints) will be advecting
northward/westward ahead of this activity. There is some potential
for this activity to remain slightly elevated given the early
morning timing and some overnight boundary layer cooling. However,
high theta-e advection will also mitigate inhibition. Though this
uncertainty remains, the Slight risk has been moved farther westward
in central Texas to account for potential near-surface/surface based
storms early on Tuesday. Additional early morning activity is
expected along the northward lifting warm front as the shortwave
trough ejects into the southern Plains and the low-level jet
impinges on the boundary.
How this morning activity evolves will greatly impact the potential
for higher-end severe storms in the afternoon and what the greatest
severe hazard will be. The very moist airmass and steep mid-level
lapse rates will promote a zone of 2500-3500 J/kg MLCAPE in parts of
Central/East Texas south of the warm front. With greater than 50 kts
of effective shear, all severe hazards would be possible regardless
of the ultimate evolution of the convection. That being said, there
appears to be a corridor of conditionally higher severe potential
near and just south of the warm front in Northeast Texas into
northwest Louisiana. Should a more organized cluster/MCS persist
through Monday night into Tuesday morning, there is greater
potential for a swath of severe wind gusts as the airmass
destabilizes ahead of it. Without the MCS, there is greater
potential for storms developing along the warm front to produce
tornadoes (perhaps strong) as the strong low-level jet and fringe of
the steeper lapse rates will overlap.
Given the weakly capped boundary layer even early in the day, there
is reasonable confidence in numerous storms, particularly along the
warm front. With large amounts of storm interference possible, on
top of potential MCS, confidence is not high enough to increase
tornado probabilities. Concerning the MCS and greater severe wind
potential, models vary greatly on the placement of this feature.
Similarly, confidence is too low for higher wind probabilities as
well. Overall, scattered to numerous storms along the warm front and
dryline in central Texas will be capable of all severe hazards. Very
large hail is most likely along the dryline or with storms that
develop along the southern edge of any MCS.
...Red River Vicinity...
Storms near the Red River and northward are more likely to be
elevated. Large hail and perhaps isolated damaging gusts could
occur. There is some tornado potential south of the Red River into
North Texas where storms will be at least near-surface based.
...Texas Panhandle...
With the upper-level low moving into parts of the Panhandle and weak
surface low in the South Plains, there is potential for moisture to
remain along a surface boundary. Several models show low 50s F
dewpoints in the region. The question will be how much surface
heating occurs. Should sufficient buoyancy develop, cold
temperatures aloft will promote potential for marginally severe hail
and isolated severe gusts in the strongest storms.
...Northern Mid-Atlantic...
With the Upper Ohio Valley cyclone moving slowly northeast, there
will be potential for another round of convection to develop near
the core of the upper low where greater surface heating occurs.
Marginally severe hail and isolated wind damage will be possible
with storms during the afternoon.
...South Texas...
Forcing for ascent will be somewhat weak during the afternoon and
storm development is not certain. Some model guidance suggests that
storms could form during the overnight near the Rio Grande Valley as
a shortwave impulse moves over South Texas and adjacent Mexico.
Large hail and severe winds would be possible with any supercells
that can develop.
..Wendt.. 05/05/2025
Read more