No watches are valid as of Thu Apr 30 21:25:02 UTC 2026.MD 0629 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR TEXAS BIG BEND INTO CONCHO VALLEY AND EDWARDS PLATEAU
Mesoscale Discussion 0629
NWS Storm Prediction Center Norman OK
0347 PM CDT Thu Apr 30 2026
Areas affected...Texas Big Bend into Concho Valley and Edwards
Plateau
Concerning...Severe potential...Watch unlikely
Valid 302047Z - 302245Z
Probability of Watch Issuance...20 percent
SUMMARY...Isolated occurrences of large hail are possible this
afternoon into early evening. A WW is not currently expected.
DISCUSSION...A small area of elevated thunderstorms is ongoing as of
2040z in the vicinity of Junction, TX, with potentially more
surface-based storm development occurring farther to the west along
the higher terrain in the vicinity of Marathon, TX. Latest objective
analysis suggests these storms are occurring in a modestly unstable
air mass, characterized by MUCAPE of 1000-1500 J/kg. Ambient wind
shear through a deep layer remains strong (e.g., effective bulk
shear magnitudes of 55-65 kt), so the potential exists for supercell
structures capable of large hail.
The current expectation is that any hail threat will remain isolated
and somewhat marginal in intensity into early evening. As such a
Severe Thunderstorm Watch isn't expected at this time.
Storm coverage and intensity may tend to increase later this evening
into tonight with the arrival of stronger forcing for ascent
attendant to a low-latitude short-wave trough moving through
northwest Mexico. Comparably greater potential for a watch will
exist at that time.
..Mead/Smith.. 04/30/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...EWX...SJT...MAF...
LAT...LON 30170316 30740284 31010033 30789863 30169856 29639905
29489991 29350047 29540093 29850136 29890264 29950298
30170316
MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH
MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN
SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0250 PM CDT Thu Apr 30 2026
Valid 302000Z - 011200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS SOUTHERN
PORTIONS OF TEXAS AND LOUISIANA...
...SUMMARY...
Thunderstorms with isolated large hail and gusty winds will be
possible mainly this evening and tonight across parts of
southwest/south-central Texas towards the middle Texas Coast, and
this afternoon across coastal/southern Louisiana.
...20Z Update...
The previous forecast (see below) remains on track, with only slight
changes made to ongoing probabilities to account for the latest
guidance consensus.
..Squitieri.. 04/30/2026
.PREV DISCUSSION... /ISSUED 1057 AM CDT Thu Apr 30 2026/
...Texas...
A mid- to upper-level trough west of northern Baja California late
this morning is forecast to quickly move east reaching Chihuahua and
southwest TX by daybreak Friday. Strong westerly mid to high-level
flow will be maintained across the southern tier of states. Surface
analysis showed a west-east oriented stalled front across south TX
eastward across coastal LA and into north FL. Widespread cloud
cover will limit diurnal heating today north of the boundary despite
a fetch of steeper 700-500 mb lapse rates being maintained across
northern Mexico and over TX in the vicinity of the Rio Grande. A
couple of stronger thunderstorms are possible through the early
afternoon from central into parts of southeast TX (reference MCD
#627 for short-term details). Farther west, ascent preceding the
shortwave trough will promote scattered showers and storms
developing over southwest TX late this evening with additional
activity (numerous in coverage) forecast to develop/spread east
towards the middle TX Coast through early Friday morning. Sufficient
MUCAPE and strong cloud-layer shear will support an isolated threat
for severe hail with any elevated supercells that can develop.
Strong to locally severe gusts may also occur as supercells
encounter greater instability across south-central to coastal TX
late tonight, even if they remain slightly elevated.
...Coastal/Southern Louisiana...
A convectively reinforced surface front is draped across
southern/coastal LA this morning, with thunderstorms ongoing to its
north. Greater instability will exist to the south of the front
across coastal LA this afternoon. Thunderstorms that develop/move
across the front later today could pose some risk for locally
damaging winds and marginally severe hail given weak to moderate
instability and strong deep-layer shear.
SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1209 PM CDT Thu Apr 30 2026
Valid 011200Z - 021200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS PARTS OF SOUTH
TEXAS INTO THE MIDDLE TEXAS COAST AND PORTIONS OF THE
CENTRAL/EASTERN GULF COAST...
...SUMMARY...
Isolated severe thunderstorm development is possible across parts of
South Texas and middle Texas coastal areas, parts of southeastern
Louisiana, and the western Florida Panhandle Friday afternoon
through Friday night.
...Synopsis...
Broad cyclonic flow aloft will persist across much of the U.S. east
of the Continental Divide on Friday. A shortwave trough will dig
through the central Plains into the Southeast through the period.
Within the subtropical jet, another shortwave trough will begin the
day in the Trans-Pecos and move eastward roughly along the Gulf
Coast. These two features will eventually phase by late afternoon
into the evening. The mid-level jet will increase in intensity in
response. At the surface, a stalled boundary will be positioned from
South Texas and eastward along the Gulf Coast. As the southern
stream trough progresses east, a weak frontal low will develop and
perhaps allow some inland advancement of upper 60s/low 70s F
dewpoints.
...South Texas/Middle Texas Coast...
Rich moisture will exist south of the surface boundary. Southward
progression of the boundary will determine how much risk of
surface-based convection there will be. Given the amount of
precipitation north of the front, there may be a tendency for most
storms to be undercut except closer to the coast. With 60+ kts of
effective shear, supercells will be possible despite modest
buoyancy/mid-level lapse rates. Where storms can remain surface
based, damaging winds and perhaps a tornado would be possible. Large
hail could occur even with storms that become slightly elevated.
...Southeast Louisiana into Florida Panhandle...
Severe potential along the central/eastern Gulf coast hinges on the
degree of inland moisture advancement. The expectation is for
low-level warm advection to increase with time and eastward extent.
This would suggest slightly higher confidence of
near-surface/surface-based storms in parts of the Florida Panhandle
to the Apalachicola vicinity. A mix of linear and supercell
structures appears possible. Damaging winds and large hail may occur
with the strongest storms. The tornado threat is more conditional,
but nonzero. This threat would be maximized with any discrete storms
that develop and move inland.
..Wendt.. 04/30/2026
SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0228 PM CDT Thu Apr 30 2026
Valid 021200Z - 031200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR SOUTHERN
GEORGIA INTO PORTIONS OF CENTRAL FLORIDA...
...SUMMARY...
Strong to marginally severe storms are possible in southern Georgia
into northern/central Florida.
...Synopsis...
A large upper trough across the eastern U.S. will continue to pivot
through the Southeast. A surface cold front will move southward into
the Florida Peninsula.
...Southern Georgia into Florida...
Rich low-level moisture (upper 60s to low 70s F dewpoints) is
expected to exist ahead of the southward-moving cold front.
Mid-level ascent will be strongest across southern Georgia and North
Florida, diminishing with southward extent. Strong flow within the
850-500 mb layer will help to organize convection. Areas that
receive greater surface heating could allow a few strong to severe
storms to develop during the late morning/afternoon. Deep-layer
shear will be strong, but will also be parallel to the front. At
least some activity may have a tendency to be undercut. Both
supercells and small clusters will be possible. Large hail and
damaging winds are the primary concerns. Low-level shear will be
greater in the morning and decrease with time as the low-level jet
moves northeast, leading to a more uncertain tornado threat.
..Wendt.. 04/30/2026
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