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
WW 0247 Status Updates
STATUS REPORT ON WW 247
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 30 ENE EKN
TO 10 NE CHO TO 45 E ORF.
..LYONS..05/27/26
ATTN...WFO...LWX...AKQ...RLX...RNK...
STATUS REPORT FOR WS 247
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
OHC009-053-079-087-105-115-163-167-272240-
OH
. OHIO COUNTIES INCLUDED ARE
ATHENS GALLIA JACKSON
LAWRENCE MEIGS MORGAN
VINTON WASHINGTON
VAC003-005-007-009-011-015-017-019-023-025-029-031-036-037-041-
045-049-053-063-067-071-079-081-083-087-089-091-093-095-111-117-
121-125-135-141-143-145-147-149-155-161-163-165-175-181-183-199-
530-540-550-570-580-590-595-620-650-660-670-678-680-690-700-710-
730-735-740-750-760-770-775-790-800-810-820-830-272240-
VA
. VIRGINIA COUNTIES INCLUDED ARE
ALBEMARLE ALLEGHANY AMELIA
AMHERST APPOMATTOX AUGUSTA
BATH BEDFORD BOTETOURT
BRUNSWICK BUCKINGHAM CAMPBELL
CHARLES CITY CHARLOTTE CHESTERFIELD
CRAIG CUMBERLAND DINWIDDIE
MD 0878 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PORTIONS OF THE PACIFIC NORTHWEST AND NORTHERN GREAT BASIN
Mesoscale Discussion 0878
NWS Storm Prediction Center Norman OK
0350 PM CDT Wed May 27 2026
Areas affected...portions of the Pacific Northwest and northern
Great Basin
Concerning...Severe potential...Watch unlikely
Valid 272050Z - 272215Z
Probability of Watch Issuance...5 percent
SUMMARY...Scattered storms on the northern periphery of a deep upper
low may pose a risk for severe wind gusts or hail.
DISCUSSION...As of 2045 UTC, regional radar imagery showed scattered
thunderstorms intensifying over portions of northern NV, eastern OR
and southwestern ID. Aided by ascent from an embedded shortwave
trough on the northern periphery of a deep upper low over the West
Coast, additional storm development/intensification is likely this
afternoon and evening. Filtered diurnal heating, relatively moist
surface conditions for May (dewpoints near 50 F) and cold
temperatures aloft are helping to support moderate destabilization
with 500-1000 J/kg of MLCAPE present. An increase in lightning and
cooling cloud tops over the last few hours suggests convection is
maturing, with several stronger updrafts noted.
50+ kt of east/southeasterly flow aloft is evident on area VADs and
RAP soundings. Veering wind profiles with northwesterly storm
motions will be sufficient for occasional storm organization into
multi cell clusters or occasional supercells. The steep low and
mid-level lapse rates will support a risk for severe/damaging gusts
given the potential for strong downdrafts. However, some hail is
also possible, especially with any rotating storms.
The primary limiting factor remains the more limited instability.
Cloud cover has lingered farther west, curtailing diurnal
destabilization. While cold mid-level temperatures will allow for
some destabilization beneath the northern parts of the upper low,
persistent storm organization may be confined to areas of better
buoyancy. Thus, some severe wind and hail risk is evident over parts
of northern NV, southeast OR, and southwestern ID through this
evening. However, confidence in a widespread sustained severe risk
is low and a WW is unlikely.
..Lyons/Gleason.. 05/27/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...PIH...MSO...BOI...LKN...OTX...PDT...REV...MFR...
STO...PQR...
LAT...LON 42892292 44412143 45481898 46131677 45731516 44211413
42801567 41421903 41122099 41242183 41392231 42892292
MOST PROBABLE PEAK WIND GUST...55-70 MPH
MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN
MD 0877 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR CENTRAL WISCONSIN
Mesoscale Discussion 0877
NWS Storm Prediction Center Norman OK
0314 PM CDT Wed May 27 2026
Areas affected...central Wisconsin
Concerning...Severe potential...Watch unlikely
Valid 272014Z - 272145Z
Probability of Watch Issuance...20 percent
SUMMARY...Strong to severe storms may pose a risk for isolated hail
or damaging gusts this afternoon and evening.
DISCUSSION...As of 2010 UTC, visible imagery showed thunderstorms
developing along a southward moving cold front over portions of
northern WI. Strong heating of a modestly moist air mass ahead of
the front has resulted in weak to moderate instability (SBCAPE
1000-2000 J/kg) amid steep low and mid-level lapse rates. Continued
heating and weak ascent from an upper trough over the Great Lakes
will aid in continued storm development along the front. Flow aloft
is not overly strong, but area RAP soundings show 25-35 kt of
deep-layer shear which could allow for modest storm organization.
The stronger updrafts will be capable of hail, with steep lapse
rates in the lowest few km potentially supporting damaging gusts.
The initial storms, likely multi cellular, should gradually mature
this afternoon given the buoyancy and steep lapse rates. While
shear is not overly strong, a few transient supercell structures
will also be possible. Hail and damaging gusts may occur with these
storms, but the lack of stronger ascent should limit coverage and
organization, keeping the threat isolated. A WW is unlikely.
..Lyons/Gleason.. 05/27/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...GRB...MKX...DLH...ARX...MPX...
LAT...LON 45649223 45648990 45528903 45078844 44468821 43768816
43398821 43118873 43138955 43329049 43749123 44779210
45189236 45649223
MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH
MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN
MD 0876 CONCERNING SEVERE THUNDERSTORM WATCH 247... FOR PORTIONS OF THE UPPER OHIO VALLEY...WEST VIRGINIA...AND THE MID ATLANTIC
Mesoscale Discussion 0876
NWS Storm Prediction Center Norman OK
0221 PM CDT Wed May 27 2026
Areas affected...portions of the upper Ohio Valley...West
Virginia...and the Mid Atlantic
Concerning...Severe Thunderstorm Watch 247...
Valid 271921Z - 272115Z
The severe weather threat for Severe Thunderstorm Watch 247
continues.
SUMMARY...The severe risk continues across WW247. Several stronger
clusters of storms have also been identified.
DISCUSSION...Afternoon radar imagery over WW247 showed scattered to
numerous thunderstorms ongoing over the watch area. The environment
remains unstable and modestly sheared, which should continue to
support the threat for damaging gusts and some hail with the
strongest storms over much of the watch area.
A corridor of locally greater severe potential is now apparent along
a convectively modified boundary stretching from central VA
northwestward into WV. Several clusters of stronger storms,
including a supercell crossing the Chesapeake Bay, have become
established along the boundary. The most unstable air mass (MLCAPE
1500-2000 J/kg) and slightly stronger flow aloft resides along and
south of the boundary, where locally enhanced convergence is also
supporting an increase in convective coverage. This will likely
support a few more robust storms with a concentrated risk for
damaging gusts from southern WV into south central VA over the next
few hours.
..Lyons.. 05/27/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...AKQ...LWX...RNK...PBZ...RLX...
LAT...LON 37938226 39128199 39318169 39568075 39468042 39267982
38527824 38237697 38297619 37187538 36647571 36867713
37498079 37588143 37708192 37848218 37938226
MOST PROBABLE PEAK WIND GUST...55-70 MPH
MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN
SPC 1630Z Day 1 Outlook
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
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.
SPC 1730Z Day 2 Outlook
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
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
SPC Day 1 Fire Weather Outlook
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...
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...
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