WW 245 SEVERE TSTM TX CW 270110Z - 271100Z
URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 245
NWS Storm Prediction Center Norman OK
810 PM CDT Tue May 26 2026
The NWS Storm Prediction Center has issued a
* Severe Thunderstorm Watch for portions of
South Texas
Coastal Waters
* Effective this Tuesday night and Wednesday morning from 810 PM
until 600 AM CDT.
* Primary threats include...
Scattered damaging winds and isolated significant gusts to 75
mph possible
Isolated very large hail events to 2 inches in diameter possible
A tornado or two possible
SUMMARY...One cluster of storms will have the potential to produce
damaging gusts of 60-75 mph, large hail of 1-2 inches in diameter
and a tornado or two across areas near and southeast of San Antonio
for the next few hours. Additional storms will likely form farther
to the southwest and move across South Texas during the
overnight/early morning hours, with continued potential for wind
damage and isolated large hail.
The severe thunderstorm watch area is approximately along and 85
statute miles east and west of a line from 70 miles northeast of
Cotulla TX to 75 miles south southwest of Alice TX. For a complete
depiction of the watch see the associated watch outline update
(WOUS64 KWNS WOU5).
PRECAUTIONARY/PREPAREDNESS ACTIONS...
REMEMBER...A Severe Thunderstorm Watch means conditions are
favorable for severe thunderstorms in and close to the watch area.
Persons in these areas should be on the lookout for threatening
weather conditions and listen for later statements and possible
warnings. Severe thunderstorms can and occasionally do produce
tornadoes.
&&
OTHER WATCH INFORMATION...CONTINUE...WW 244...
AVIATION...A few severe thunderstorms with hail surface and aloft to
2 inches. Extreme turbulence and surface wind gusts to 65 knots. A
few cumulonimbi with maximum tops to 550. Mean storm motion vector
28025.
...Thompson
WW 0246 Status Updates
STATUS REPORT ON WW 246
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 25 SSW VCT
TO 15 N PSX TO 40 NW HOU.
FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 0872
..WEINMAN..05/27/26
ATTN...WFO...HGX...
STATUS REPORT FOR WS 246
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
TXC039-157-321-481-270840-
TX
. TEXAS COUNTIES INCLUDED ARE
BRAZORIA FORT BEND MATAGORDA
WHARTON
GMZ330-350-270840-
CW
. ADJACENT COASTAL WATERS INCLUDED ARE
MATAGORDA BAY
COASTAL WATERS FROM FREEPORT TO MATAGORDA SHIP CHANNEL TX OUT 20
NM
THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE
REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL
INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES
WW 0245 Status Updates
STATUS REPORT ON WW 245
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 70 SSE DRT
TO 30 SE COT TO 35 ESE NIR TO 25 ENE VCT.
FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 0871
..WEINMAN..05/27/26
ATTN...WFO...CRP...EWX...BRO...
STATUS REPORT FOR WS 245
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
TXC007-047-057-131-247-249-261-273-283-297-311-355-391-409-427-
479-505-270840-
TX
. TEXAS COUNTIES INCLUDED ARE
ARANSAS BROOKS CALHOUN
DUVAL JIM HOGG JIM WELLS
KENEDY KLEBERG LA SALLE
LIVE OAK MCMULLEN NUECES
REFUGIO SAN PATRICIO STARR
WEBB ZAPATA
GMZ135-155-231-232-236-237-250-255-270840-
CW
. ADJACENT COASTAL WATERS INCLUDED ARE
LAGUNA MADRE FROM 5 NM NORTH OF PORT MANSFIELD TO BAFFIN BAY TX
COASTAL WATERS FROM BAFFIN BAY TO PORT MANSFIELD TX OUT 20 NM
MD 0873 CONCERNING SEVERE THUNDERSTORM WATCH 245... FOR PORTIONS OF SOUTH TEXAS
Mesoscale Discussion 0873
NWS Storm Prediction Center Norman OK
0406 AM CDT Wed May 27 2026
Areas affected...Portions of South Texas
Concerning...Severe Thunderstorm Watch 245...
Valid 270906Z - 271100Z
The severe weather threat for Severe Thunderstorm Watch 245
continues.
SUMMARY...The risk of large hail and severe wind gusts continues
with a cluster of storms over South Texas -- within Severe
Thunderstorm Watch 245.
DISCUSSION...A cluster of thunderstorms is evolving along the
east/west-oriented portion of an outflow boundary extending across
South TX. Here, steep midlevel lapse rates (around 7.5 C/km per
earlier 00Z observed soundings) atop rich boundary-layer moisture
(middle/upper 60s to lower 70s dewpoints) are contributing to
moderate instability -- even immediately north of the outflow
boundary. This instability and around 40 kt of effective shear will
continue to promote loosely organized convective clusters capable of
producing large hail and severe wind gusts. A gust of 58 mph was
recently measured in Laredo TX at 0841 UTC. Given recent radar
trends and cold pool evolution with respect to the
west-southwesterly deep-layer shear, there is some potential that a
forward-propagating cluster of storms tracks east-southeastward
along the outflow boundary. This evolution would increase the risk
of severe wind gusts.
..Weinman.. 05/27/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...CRP...BRO...
LAT...LON 27339836 26989856 26819902 26889952 27519963 27789982
28029969 28189935 28239894 28109855 27829826 27339836
MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 90 MPH
MOST PROBABLE PEAK WIND GUST...55-70 MPH
MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN
SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1254 AM CDT Wed May 27 2026
Valid 271200Z - 281200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE MID-ATLANTIC...
...SUMMARY...
Thunderstorms with severe wind gusts will be possible today across
parts of the Mid-Atlantic and Ohio Valley. Isolated wind gusts and
hail will also be possible in the western Great Lakes and from the
southern Texas Panhandle into west Texas and far western Oklahoma.
...Mid-Atlantic/Ohio Valley...
An upper-level trough will move southeastward today across the Great
Lakes. Flow ahead of the trough will be westerly over the Ohio
Valley and Mid-Atlantic. At the surface, a cold front will move
southward into the Ohio Valley. South of the front, dewpoints in the
60s F will contribute to pockets of moderate instability by
afternoon. As low-level convergence and instability maximizes near
the front, thunderstorms are expected to form and move
east-southeastward across the Ohio Valley and Mid-Atlantic.
RAP forecast soundings just ahead of the front in northern Virginia
at 21Z have MLCAPE near 1200 J/kg with 0-6 km shear around 40 knots.
This will support organized thunderstorms, potentially in the form
of multiple short severe line segments. During the mid to late
afternoon, low-level lapse rates are forecast to peak near 7.5 C/km,
which will be favorable for a wind-damage threat. Hail will also be
possible within the stronger cores.
...Western Great Lakes...
Northwesterly mid-level flow will be in place across the western
Great Lakes today, as a shortwave trough moves southeastward across
the region. At the surface, a pocket of maximized low-level moisture
will be located over Wisconsin, where MLCAPE is expected to peak in
the 1500 to 2500 J/kg range. Thunderstorms that form during the
afternoon that have access to moderate instability and steep
low-level lapse rates could have potential for isolated wind gusts.
Hail could also occur.
...Southern Texas Panhandle/West Texas/Far Western Oklahoma...
At low-levels, a moist and unstable airmass is forecast to advect
northward across west Texas into the southern Texas Panhandle today.
A zone of low-level convergence will likely develop over the
southern Texas Panhandle, with upslope flow to the north of this
feature. As surface temperatures warm during the day, scattered
thunderstorm development is expected near the convergence zone. RAP
forecast soundings to the south and east of Amarillo at 21Z have
steep low to mid-level lapse rates with large surface
temperature-dewpoint spreads. This may be enough for isolated severe
wind gusts and hail.
..Broyles/Chalmers.. 05/27/2026
SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1225 AM CDT Wed May 27 2026
Valid 281200Z - 291200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM CENTRAL
OREGON INTO EASTERN WASHINGTON...NORTHERN IDAHO AND NORTHWEST
MONTANA...
...SUMMARY...
Isolated severe storms are possible on Thursday over western
Montana, northern Idaho, and into central Oregon/Washington. A few
damaging gusts or marginal hail will be possible.
...Synopsis & Discussion...
An upper low will move slowly from CA into NV on Thursday, with a
leading midlevel speed max forecast to move from UT northward across
ID, OR and WA. Cooling aloft will occur along with 40-50 kt 500 mb
winds enhancing deep-layer shear. A surface trough will also deepen
during the afternoon roughly from UT into eastern WA, with strong
heating and steepening lapse rates aiding destabilization.
Scattered storms are forecast to develop by early afternoon over
central OR, with additional activity extending northeastward across
northern ID, eastern WA and northwest MT. Though total CAPE values
are questionably high by some models, sufficient instability will
exist, along with favorable large-scale ascent and steep lapse
rates. This will favor northwestward-moving cells and perhaps a few
bows, with at least isolated severe gusts or marginal hail expected.
Elsewhere, scattered storms are likely during the afternoon and
evening from KS/OK into the Southeast. Winds aloft and shear will be
weak across this entire region, and severe storms are largely not
expected. Still, sporadic strong gusts cannot be ruled out.
..Jewell.. 05/27/2026
SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0214 AM CDT Wed May 27 2026
Valid 291200Z - 301200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM EASTERN NEW
MEXICO INTO WESTERN TEXAS...AND OVER WESTERN MONTANA...
...SUMMARY...
A few storms may produce large hail from eastern New Mexico into
western Texas on Friday. Strong storms may also occur across western
Montana with gusty winds and marginal hail.
...Southern High Plains...
Modest westerly flow aloft will spread across NM and into TX, with
cool midlevel temperatures resulting in steep lapse rates. A surface
trough will be situated over far eastern NM, and scattered storms
are likely to develop during the afternoon with 50s to near 60 F
dewpoints. Up to 30 kt deep-layer shear and ample
moisture/instability may support a few severe slow-moving cells
producing large hail. These storms will likely spread into the TX
Panhandle/South Plains during the evening, with localized wind
potential as well.
...Western MT...
An upper low/shortwave trough will move eastward across the Great
Basin on Friday, taking on a negative tilt. Extending north of this
low will be a belt of 30 kt southerly winds around 500 mb, with a
bit stronger speeds in the upper levels. A surface trough will
deepen over central MT, with a cold front pushing across western MT.
The cool temperatures aloft/steep lapse rate environment should
support at least marginal hail, while favorable afternoon timing
with boundary layer mixed layers will support strong downdrafts.
This should result in at least isolated strong to severe cells
moving northeastward across western MT during the afternoon.
..Jewell.. 05/27/2026
Day 4-8 Outlook
Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0246 AM CDT Wed May 27 2026
Valid 301200Z - 041200Z
...DISCUSSION...
On Saturday/D4, an upper low will weaken as it moves from UT into
WY, with midlevel wind speeds at or below 25 kt across the northern
Rockies/Plains. This feature will persist into Sunday/D5 and
Monday/D6 as it moves toward MT and eventually into Canada. Given
the weak winds aloft, severe potential should be relatively low, but
isolated strong storms may occur over parts of the northern Plains.
Farther south, stronger instability is forecast over the southern
and central Plains, where 60s to lower 70s F dewpoints will exist.
Although unstable, shear will be quite weak. Saturday/D4 may hold
slightly greater severe potential compared to other days, as the
southern lobe of the western trough lifts north out of the
southern/central Plains. However, shear will still be marginal, and
the likelihood antecedent precip/outflows lessens predictability in
the weak forcing pattern. The stronger instability air mass appear
most prominent through about Monday/D6. Thereafter, an upper trough
may amplify over the eastern CONUS, driving high pressure south
across the eastern CONUS/MS Valley.
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1235 AM CDT Wed May 27 2026
Valid 271200Z - 281200Z
...Synopsis...
An upper level low will hover over the CA/Great Basin region today
as an upper ridge will continue to reside across the central CONUS.
Strengthening southerly flow aloft and tightening surface pressure
gradients east of a persisting surface low will promote a fire
weather threat for portions of the Southwest and Upper Colorado
River Basin. Farther east, a weak shortwave is expected to eject
across the central and southern Plains, bringing additional chances
of appreciable precipitation to a drought-stressed landscape.
...Great Basin...
Broad southwesterly flow associated with the hovering upper low will
sustain fire weather concerns for portions of the eastern Great
Basin, Upper CO River Basin, and parts of the Southwest. Southerly
surface winds of 15-25 mph and RH reductions of 10-20% will promote
Elevated to locally critical fire weather conditions this afternoon
amid available dry fuels.
...Northeastern Montana...
Prolonged lee surface troughing and increasing mid level flow will
promote strong southeasterly winds of 15-25 mph across the northern
High Plains. Despite some upper level cloud cover, a deep and
well-mixed boundary layer will support RH reductions of 15-20%
across northeastern MT and extreme western ND. Elevated highlights
have been slightly trimmed to exclude where appreciable 12-24h
precipitation has fallen.
..Elizalde-Garcia.. 05/27/2026
...Please see www.spc.noaa.gov/fire for graphic product...
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1236 AM CDT Wed May 27 2026
Valid 281200Z - 291200Z
...Synopsis...
A similar synoptic setup as D1/Wednesday will carry over into
D2/Thursday as a nearly stationary upper low remains over CA/Great
Basin, and upper ridging persists across the central CONUS. The main
trough axis will gradually lift into the central Plains while
moisture advection occurs downstream of the upper low, encouraging
continued chances for precipitation in the High Plains. Beneath
upper troughing, a cold front is expected to progress southward
across the Mid-Atlantic bringing below-normal temperatures and
additional opportunities for spotty precipitation to the Eastern
Seaboard.
...Great Basin and Southwest...
Prolonged southwesterly flow will maintain fire weather concerns for
parts of the Great Basin, Upper CO River Basin, and portions of the
Southwest through Day 2/Thursday. Southerly sustained winds of 15-25
mph and RH values around 15% combined with drier lower elevation
fuels are expected to promote Elevated fire weather conditions
during the afternoon.
...Northeastern Montana...
Ahead of a persistent surface trough, dry southeasterly flow over
the northern High Plains will support another day of enhanced fire
weather concerns across northeastern MT on Day 2/Thursday. Elevated
highlights have been introduced to northeastern MT where receptive
fuels are still present within pockets of green up.
..Elizalde-Garcia.. 05/27/2026
...Please see www.spc.noaa.gov/fire for graphic product...
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