RSS Mesoscale Discussions from Storm Prediction Center
WW 247 SEVERE TSTM MD OH VA WV CW 271710Z - 280100Z
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
Read more
WW 0247 Status Updates
STATUS REPORT ON WW 247
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 30 NNE HTS
TO 45 WSW EKN TO 30 S EKN TO 5 SE SHD TO 15 SSW CHO TO 25 SSE CHO
TO 20 E RIC TO 60 ENE ORF.
FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 0880.
..MEAD..05/27/26
ATTN...WFO...LWX...AKQ...RLX...RNK...
STATUS REPORT FOR WS 247
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
OHC087-280040-
OH
. OHIO COUNTIES INCLUDED ARE
LAWRENCE
VAC005-007-009-011-015-017-019-023-025-029-031-036-037-041-045-
049-053-063-067-071-081-083-087-089-091-093-095-111-117-121-125-
135-141-143-145-147-149-155-161-163-175-181-183-199-530-550-570-
580-590-595-620-650-670-678-680-690-700-710-730-735-740-750-760-
770-775-790-800-810-820-830-280040-
VA
. VIRGINIA COUNTIES INCLUDED ARE
ALLEGHANY AMELIA AMHERST
APPOMATTOX AUGUSTA BATH
BEDFORD BOTETOURT BRUNSWICK
BUCKINGHAM CAMPBELL CHARLES CITY
CHARLOTTE CHESTERFIELD CRAIG
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MD 0880 CONCERNING SEVERE THUNDERSTORM WATCH 247... FOR WEST VIRGINIA INTO CENTRAL AND SOUTHERN PARTS OF VIRGINIA
Mesoscale Discussion 0880
NWS Storm Prediction Center Norman OK
0554 PM CDT Wed May 27 2026
Areas affected...West Virginia into central and southern parts of
Virginia
Concerning...Severe Thunderstorm Watch 247...
Valid 272254Z - 280100Z
The severe weather threat for Severe Thunderstorm Watch 247
continues.
SUMMARY...Isolated damaging wind gusts remain most likely across
portions of central and southern Virginia over the next couple of
hours.
DISCUSSION...As of 22:45 UTC a broken band of strong to severe
storms was ongoing from northeast of Roanoke to west of Richmond,
with a storm motion of 282/38 kt. Latest surface analysis and
visible satellite indicate a corridor of less-dense cloud cover to
the south of the ongoing storms, where temperatures remain in the
low/mid 80s with dewpoints in the upper 60s to low 70s. Resultant
MLCAPE is estimated in the 1000-1500 J/kg range within that corridor
with relatively steep low-level lapse rates. Area VWPs indicate
westerly winds above 1 km AGL with 30-35 kt of deep-layer shear,
which will continue to support some storm organization for the next
couple of hours with the primary hazard being locally damaging wind
gusts.
Cooling boundary-layer temperatures and a corresponding increase in
air mass stability are expected to lead to an increasingly sporadic
severe threat by 01z.
..Mead.. 05/27/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...AKQ...LWX...RAH...RNK...RLX...JKL...ILN...
LAT...LON 36538052 37248091 37268172 37708227 38348270 38928276
39248252 39248171 39218081 38917955 38687880 38237835
38017838 37797834 37657782 37537723 37317642 37137598
36927550 36617555 36487699 36538052
MOST PROBABLE PEAK WIND GUST...55-70 MPH
MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN
Read more
MD 0879 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PORTION OF EASTERN OKLAHOMA INTO CENTRAL/SOUTHERN ARKANSAS
Mesoscale Discussion 0879
NWS Storm Prediction Center Norman OK
0508 PM CDT Wed May 27 2026
Areas affected...portion of eastern Oklahoma into central/southern
Arkansas
Concerning...Severe potential...Watch unlikely
Valid 272208Z - 280015Z
Probability of Watch Issuance...5 percent
SUMMARY...A few strong thunderstorms may bring a low-end risk for
isolated gusty winds and perhaps a brief tornado through this
evening. Watch issuance is not expected.
DISCUSSION...As of 2200 UTC, regional radar imagery depicted
scattered thunderstorms extending from eastern Oklahoma into
central/southern Arkansas immediately downstream of a mid-level
perturbation and in close proximity to a surface low analyzed near
the Red River. A couple of storms have shown signs of transient,
weak rotation and/or modestly enhanced velocity signatures over the
past hour. Expectation is for this activity to continue for another
few hours amid a moist and weak to modestly unstable environment
(MLCAPE of 1000-1500+ J/kg). While marginal deep-layer shear
(generally less than 30 kts) and poor mid-level lapse rates, as
sampled by the 18z SHV observed sounding, are largely expected to
temper updraft intensity, high precipitable water contents
(1.75-2.00+ inches per latest mesoanalysis) may promote occasional
water-loaded downdrafts capable of isolated gusty winds (largely in
the 40-45 mph range). A brief tornado also cannot be ruled out,
especially where a stronger low-level updraft can interact with
marginally enhanced low-level shear to the north-northeast of the
surface low. Given the expectation for any severe threat to remain
isolated and limited in magnitude, a WW is unlikely.
..Chalmers/Guyer.. 05/27/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...LZK...SHV...TSA...OUN...
LAT...LON 33349352 33839395 34119450 34489535 34579588 34629611
34819626 34999637 35449636 35759624 35989594 36129550
36139465 35989397 35779343 35329282 34899240 34529225
33969207 33469212 33199226 33029250 32879294 33009321
33349352
MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 90 MPH
MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH
Read more
SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0251 PM CDT Wed May 27 2026
Valid 272000Z - 281200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE
OHIO VALLEY AND MID ATLANTIC...
...SUMMARY...
Scattered severe thunderstorms remain 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.
...20Z Update...
The previous forecast (see below) remains generally on track (please
see MCD 876 for short-term severe trends in the Mid-Atlantic
region). The primary change to the outlook was to drop severe wind
and hail probabilities across the TX Panhandle. Here, convection has
failed to deepen, with widespread cloud cover becoming more
prevalent during the diurnal heating maximum. It is unclear if cells
can congeal into larger storm cores capable of producing severe wind
and hail. However, enough overlapping vertical oriented low-level
vorticity and 0-3 km CAPE exists to support a landspout, so 2
percent tornado probabilities have been maintained given the
presence of convective updrafts.
..Squitieri.. 05/27/2026
.PREV DISCUSSION... /ISSUED 1120 AM CDT Wed May 27 2026/
...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.
Read more
SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0230 PM CDT Wed May 27 2026
Valid 291200Z - 301200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS WESTERN
MONTANA...THE CENTRAL HIGH PLAINS...AND THE SOUTHERN HIGH PLAINS
INTO SOUTHERN ARKANSAS AND NORTHERN LOUISIANA....
...SUMMARY...
Isolated to scattered storms may produce large hail from eastern New
Mexico and western Texas into southern Arkansas and northern
Louisiana on Friday. Strong to severe storms may also occur across
western Montana with gusty winds and marginal hail. Damaging
thunderstorm wind gusts are also possible across portions of the
central High Plains.
...Synopsis...
A closed low across the Great Basin will become an open wave and
start to advance northeast toward the central Rockies. As this
occurs, lee troughing will begin across the southern and central
High Plains and into eastern Montana. A strong mid-level trough will
move southward across eastern Canada into the Northeast.
...Western Montana...
Weak to moderate instability will build across western Montana on
Friday as dewpoints increase into the mid 50s and mid-level
temperatures cool. Mid-level flow is forecast to increase to 30 to
40 knots across western Montana which will provide sufficient shear
for storm organization. The Marginal Risk was expanded slightly to
account for the likely extent of the threat given the 12Z guidance.
...Central Plains...
Surface moisture is forecast to back up near the terrain across
northern Colorado and southeast Wyoming. This will lead to weak to
moderate instability across the region. In addition to typical
terrain circulations, guidance suggests a weak mid-level shortwave
trough may emerge across the region and provide additional support
for storm development. Shear is forecast to remain relatively weak,
but weak to moderate instability, and steep lapse rates will support
some threat for severe wind gusts.
...Southern Plains into southern Arkansas and northern Louisiana...
A southern stream mid-level jet streak is forecast to emerge from
northern Mexico into the southern High Plains. This ~40 knot jet
streak will overspread portions of the southern High Plains and the
dryline. This should provide ample shear for storm organization
during the afternoon/evening. Greater storm coverage and severe
potential may exist between Midland and Lubbock at the nose of this
stronger mid-level flow. However, there is still some uncertainty
with the timing/location of this jet streak, so will not add higher
probabilities at this time.
Added 5% probabilities farther east across Oklahoma and into
southern Arkansas and northern Louisiana. Moderate instability is
expected south of a frontal zone in this general area. This may be a
focus for storm development Friday afternoon/evening. Shear may be
somewhat weak, but the instability and frontal focus could support a
few strong to severe storms.
..Bentley.. 05/27/2026
Read more
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0229 PM CDT Wed May 27 2026
Valid 281200Z - 291200Z
...Great Basin and Southwest...
An upper-level low anchored over the Sierra Nevada and corresponding
surface low over western ID will continue to pose a fire weather
threat to portions of the Great Basin and Southwest D2/Thursday.
Breezy south winds of 15-25 mph, relative humidity as low as 10% in
valleys and dry/cured fuels in lower elevations will support an
enhanced fire weather concern across portions of AZ and far western
NM into the eastern Great Basin and CO Western Slope. Elevated
highlights were extended northward into far southern ID where recent
fire activity amid locally drier fuels exist. Additional expansion
farther into central UT was warranted based on latest forecast
guidance.
...Northeastern Montana...
Surface troughing extending from ID into the Northern Rockies and
surface high pressure settling into the Great Lakes will maintain a
dry southeasterly flow across portions of the northern High Plains
D2/Thursday. The alignment of receptive fuels, southeast winds of
15-20 mph and daytime relative humidity around 20% will support
elevated fire weather conditions across northeastern MT.
..Williams.. 05/27/2026
.PREV DISCUSSION... /ISSUED 1236 AM CDT Wed May 27 2026/
...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.
...Please see www.spc.noaa.gov/fire for graphic product...
Read more
SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0411 PM CDT Wed May 27 2026
Valid 291200Z - 041200Z
...Synopsis...
An upper-level low over the Great Basin will evolve into an open
wave Friday before accelerating northeastward towards the Northern
Plains over the weekend. A blocking ridge across the central U.S.
will persist while several mid-level short wave troughs traverse
across the Northeast through early next week. Fire weather concerns
will remain minimal through the middle of next week over much of the
CONUS, although warmer and drier conditions moving in behind the
exiting upper-low will promote drying of fuels across the Southwest.
...Day 3/Friday - Four Corners and Colorado Plateau...
A mid-level jet will move into the Four Corners region as an
upper-level trough over the Great Basin begins to translate
northeastward Day 3/Friday. Residual dry, southerly flow across the
Four Corners and Southwest is expected to bring a continued fire
weather threat to portions of the Four Corners and Colorado Plateau
where lower elevated fuels remain receptive. The 40% critical
probability area has been expanded southward into the Four Corners
where recent rainfall was minimal.
...Day 4-8/Saturday-Wednesday...
The exit of the upper trough and muted surface pressure gradients
will promote a warming and drying trend across the Southwest through
early next week. Ample rainfall and cooler temperatures across the
Southern Plains and Southeast will minimize fire weather concerns.
Persistent surface high pressure the Great Lakes should allow for
lighter winds and mainly dry conditions to limit fire weather
concerns through early next week, although this pattern will bolster
the drying of fuels over the region into the Upper Midwest. Longer
term model guidance suggests deeper moisture aided by the presence
of a diffuse upper low setting up near Baja California, returns to
portions of the Southwest by the middle of next week. With several
preceding days of warm and dry conditions, fuels could become more
receptive to lightning ignition from initially high-based
thunderstorms. Too much uncertainty remains for Day 8/Wednesday to
include dry thunderstorm probabilities at this time.
..Williams.. 05/27/2026
...Please see www.spc.noaa.gov/fire for graphic product...
Read more
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