URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 247
NWS Storm Prediction Center Norman OK
110 PM EDT Wed May 27 2026

The NWS Storm Prediction Center has issued a

* Severe Thunderstorm Watch for portions of 
  Southern Maryland
  Southeast Ohio
  Virginia
  West Virginia
  Coastal Waters

* Effective this Wednesday afternoon and evening from 110 PM
  until 900 PM EDT.

* Primary threats include...
  Scattered damaging wind gusts to 65 mph likely
  Isolated large hail events to 1.5 inches in diameter possible

SUMMARY...Scattered to numerous thunderstorms are expected to pose a
threat for mainly damaging winds as this activity moves
east-southeastward through the afternoon and evening. Peak gusts may
reach up to 60-65 mph. Isolated hail may also occur with the
strongest cores.

The severe thunderstorm watch area is approximately along and 60
statute miles north and south of a line from 40 miles west northwest
of Charleston WV to 40 miles south southeast of Wallops VA. For a
complete depiction of the watch see the associated watch outline
update (WOUS64 KWNS WOU7).

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.

&&

AVIATION...A few severe thunderstorms with hail surface and aloft to
1.5 inches. Extreme turbulence and surface wind gusts to 55 knots. A
few cumulonimbi with maximum tops to 500. Mean storm motion vector
29030.

...Gleason

STATUS FOR WATCH 0247 HAS NOT BEEN ISSUED YET

Mesoscale Discussion 0875
NWS Storm Prediction Center Norman OK
1131 AM CDT Wed May 27 2026

Areas affected...portions of the Ohio valley and Mid Atlantic

Concerning...Severe potential...Watch possible 

Valid 271631Z - 271830Z

Probability of Watch Issuance...60 percent

SUMMARY...Scattered to numerous thunderstorms are expected this
afternoon across parts of southern OH and northeastern KY into WV
and the DelMarVA. A mixed storm mode should promote a risk for
damaging gusts, though some hail is also possible. One or more
severe thunderstorm watches will probably be issued in the next
couple of hours.

DISCUSSION...As of 1630 UTC, visible and radar imagery showed
initial thunderstorms gradually intensifying over the OH Valley with
clearing and deepening cumulus farther east. Weak ascent from a
broad upper trough over the northern Great Lakes is overspreading an
east-west frontal zone amidst midday heating. To the south of the
front, a very moist air mass is in place with dewpoints in the low
70s F. As surface temperatures warm near 80 F, destabilization
should continue this afternoon. Despite modest mid-level lapse
rates, 1000-1500 J/kg of MLCAPE and little inhibition will allow for
scattered to widespread thunderstorms.

A belt of enhanced westerly flow associated with the upper trough
will continue to shift eastward near the front supporting modest
deep-layer shear around 20-25 kt. Initial storms over OH and KY are
likely to be multi cellular with brief organization potential and
some clustering. As deep-layer shear increases to 30-35 kt over WV
and the Mid Atlantic states, a few marginal supercell structures and
some linear segments are also possible.

As thunderstorms develop and eventually cluster, damaging gust
potential should increase this afternoon over the OH Valley, with
additional development and the severe threat spreading eastward with
time. The brief stronger updrafts may also pose a risk for some
hail, but mid-level temperatures and lapse rates are not overly
favorable. Hail potential may be maximized with any storms that
remain more discrete.

Confidence in a sustained severe risk is highest farther east where
the best overlap of deep-layer shear and buoyancy are expected
(WV/VA into southern MD/DE). Given the expected increase in severe
potential this afternoon, a WW is possible in the next couple of
hours.

..Lyons/Gleason.. 05/27/2026

...Please see www.spc.noaa.gov for graphic product...

ATTN...WFO...AKQ...LWX...RAH...RNK...PBZ...RLX...JKL...ILN...

LAT...LON   37388207 38458274 38908272 39778148 39838111 39277960
            38747775 38487633 38387501 36917591 36317558 36257640
            36407905 37388207 

MOST PROBABLE PEAK WIND GUST...55-70 MPH
MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN

Day 1 Convective Outlook  
NWS Storm Prediction Center Norman OK
1120 AM CDT Wed May 27 2026

Valid 271630Z - 281200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE OHIO VALLEY INTO THE MID-ATLANTIC...

...SUMMARY...
Scattered severe thunderstorms are possible across parts of the Ohio
Valley and Mid-Atlantic this afternoon and evening. Strong to severe
gusts capable of producing wind damage should be the primary hazard,
but isolated hail may also occur.

...Ohio Valley/Mid-Atlantic...
30-40 kt of mid-level westerly flow will be present today across
parts of the OH Valley and Mid-Atlantic, sandwiched between an upper
trough over Ontario/Quebec and a mid-level anticyclone centered over
the western Atlantic. A west-east oriented front, modulated by
ongoing convection, will serve as a focus and northern limit for
severe potential. Latest surface observations show a rather moist
low-level airmass present along/south of this boundary (also
reference the 12Z observed soundings from IAD/RNK), with surface
dewpoints generally in the mid 60s to low 70s. Lapse rates aloft are
expected to remain poor, and persistent cloud cover will slow
daytime heating.

Still, weak to moderate instability (MLCAPE 500-1500 J/kg) coupled
with 30-40 kt of westerly deep-layer shear will support organized
thunderstorms this afternoon and early evening as a weak mid-level
shortwave trough moves eastward across the OH Valley/Mid-Atlantic. A
mix of multicells and marginal supercell structures is anticipated
along/south of the front, with scattered damaging winds the main
severe risk. Some hail could also occur with the strongest cores.
The Slight Risk for severe/damaging winds has been expanded westward
into parts of WV and vicinity, where a favorable
environment/convective evolution should occur, similar to locations
farther east in VA/MD along/south of ongoing precipitation.

...Pacific Northwest/Northern Rockies...
A closed mid/upper-level low is not expected to move much over CA/NV
today. Enhanced east-southeasterly mid-level flow and modest
large-scale ascent to the north of this cyclone will likely support
isolated to widely scattered thunderstorms this afternoon and
evening across parts of OR/ID and western MT. Cool temperatures
aloft and adequate low-level moisture should support at least weak
instability as filtered daytime heating occurs. As low-level lapse
rates steepen with the well-mixed boundary layer, isolated severe
gusts appear possible with the high-based convection that develops
and spreads west-northwestward through the afternoon/evening. Some
gusts may reach up to 70-75 mph on a localized basis, but confidence
in a more focused corridor of severe winds remains too low to
include greater probabilities at this time. Isolated hail may also
occur.

...Coastal Texas to the ArklaTex...
An expansive MCS has moved offshore from coastal TX into the western
Gulf late this morning. A leading MCS/outflow is also present across
parts of southern/central LA. Current expectations are for limited
redevelopment and severe risk through the period in the wake of this
ongoing activity across coastal TX/southern LA. However, there may
be an opportunity for modest destabilization near an MCV across the
ArkLaTex vicinity this afternoon. Favorable/veering wind profiles
with height through mid levels and related deep-layer shear (see
recent VWPs from KSHV) would conditionally support organized
thunderstorms this afternoon, assuming sufficient instability can
develop amid widespread cloud cover. Have opted to add a focused
Marginal Risk across portions of the ArkLaTex and vicinity for this
potential, with both occasional damaging winds and a tornado or two
possible with the stronger cells that develop.

...Upper Midwest/Western Great Lakes...
Modest north-northwesterly mid-level flow should exist today across
the Upper Midwest and western Great Lakes. With continued daytime
heating, moderate instability should develop along/south of a weak
surface front. Thunderstorms that initiate along/near the front this
afternoon could pose an isolated threat for severe hail and damaging
winds, particularly across parts of WI where the best convective
signal exists in various short-term model guidance. However, overall
convective coverage is uncertain, as large-scale ascent should
remain fairly weak.

...Southern High Plains...
Cool temperatures aloft in association with a weak mid-level trough
over the southern High Plains should aid at least weak
destabilization this afternoon across parts of northwest TX into the
TX Panhandle and far western OK. While low-level moisture will
remain fairly muted and deep-layer shear rather modest, a few
stronger thunderstorms capable of producing isolated hail/gusty
winds and perhaps a landspout may occur.

..Gleason/Lyons.. 05/27/2026

Day 2 Convective Outlook  
NWS Storm Prediction Center Norman OK
1230 PM CDT Wed May 27 2026

Valid 281200Z - 291200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF
THE COLUMBIA BASIN...

...SUMMARY...
Scattered severe storms are possible on Thursday over portions of
the Columbia Basin with more isolated storms across the broader
Northwest region. Damaging winds will be the primary threat, with
some threat for large hail.

...Synopsis...
A mid-level shortwave trough currently on the western periphery of
the broader mid-level low across California at mid-day Wednesday
will move around the low-pressure center and emerge across the
Northwest on Thursday. East of this low, a strong mid-level ridge
will be maintained across the central CONUS with a mid-level trough
in the east. This pattern will result in a mostly nebulous surface
pattern other than a more defined area of high pressure across the
Great Lakes.

...Northwest...
Low-level moisture will increase across the Columbia Basin Wednesday
and Thursday, primarily from the northeasterly surface flow. This
moisture, combined with cooling air aloft and robust surface
heating, will result in abnormally large instability across the
region. In fact, the GFS/NAM/RAP forecast soundings show record-high
MLCAPE values at OTX tomorrow afternoon. Given the climatological
extreme of these values, it seems unlikely to be as high as forecast
(1500-2000 J/kg). However, even 750-1000 J/kg MLCAPE would result in
an environment favorable for severe storms, particularly across
northern Oregon and south-central Washington where even the HRRR
shows 1000 to 1200 J/kg MLCAPE. Very steep mid-level lapse rates
(near 9 C/km) and moderate shear will also support organized severe
storms. 

The timing of the mid-level shortwave trough emerging across Oregon
appears to be well-timed with afternoon peak heating. Therefore,
expect storms to initially form across east-central Oregon and move
north-northwestward through the evening. Most 12Z CAM guidance shows
upscale growth into a linear segment which would likely support a
damaging wind threat, particularly given the steep lapse rate
environment. For these reasons, have upgraded to a Level 2 Slight
Risk across portions of the Columbia Basin. 

Expanded the wind probabilities across the Cascades slightly as the
environment appears to be favorable to the west of the crests.
However, it appears the marine layer should move into areas such as
Portland prior to the arrival of the storms. Therefore, have kept
severe probabilities east of this zone where the marine layer will
likely have a stabilizing effect.

..Bentley.. 05/27/2026

Day 1 Fire Weather Outlook  
NWS Storm Prediction Center Norman OK
1120 AM CDT Wed May 27 2026

Valid 271700Z - 281200Z

...Great Basin and portions of the Southwest...
A 50-60 kt mid-level jet on the eastern periphery of an upper-low
centered over the Sierra Nevada will remain anchored over eastern NV
and western UT today into Day 2/Thursday. Recent downslope enhanced
wind gusts of 50-60 mph have been observed across southwestern UT.
Further boundary layer mixing today will yield minimum RH of 10-20%
across portions of the Southwest and eastern Great Basin. Widespread
southerly winds of 15-25 mph (locally higher in downslope favored
areas) developing through peak afternoon heating along with low RH
and drying/cured lower elevation fuels, will result in elevated fire
weather conditions today. A slight northward expansion of Elevated
Highlights was warranted across central UT in the lee of the central
UT mountain chain based current observation trends and latest short
term forecast guidance.

Otherwise, the forecast remains on track for northeastern MT. Please
see previous discussion for more details.

..Williams.. 05/27/2026

.PREV DISCUSSION... /ISSUED 1235 AM CDT Wed May 27 2026/

...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.

...Please see www.spc.noaa.gov/fire for graphic product...