RSS Mesoscale Discussions from Storm Prediction Center
WW 237 SEVERE TSTM TX 202015Z - 210300Z
URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 237
NWS Storm Prediction Center Norman OK
315 PM CDT Wed May 20 2026
The NWS Storm Prediction Center has issued a
* Severe Thunderstorm Watch for portions of
Southwest Texas
* Effective this Wednesday afternoon and evening from 315 PM
until 1000 PM CDT.
* Primary threats include...
Scattered large hail and isolated very large hail events to 2
inches in diameter likely
Scattered damaging wind gusts to 70 mph possible
A tornado or two possible
SUMMARY...Intense thunderstorms will develop off the Davis Mountains
and spread eastward this afternoon and evening, posing a risk of
large hail and damaging wind gusts.
The severe thunderstorm watch area is approximately along and 60
statute miles north and south of a line from 15 miles south
southwest of Marfa TX to 35 miles east northeast of Dryden TX. 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.
&&
OTHER WATCH INFORMATION...CONTINUE...WW 234...WW 235...WW 236...
AVIATION...A few severe thunderstorms with hail surface and aloft to
2 inches. Extreme turbulence and surface wind gusts to 60 knots. A
few cumulonimbi with maximum tops to 500. Mean storm motion vector
25025.
...Hart
Read more
WW 236 SEVERE TSTM KY OH VA WV 201950Z - 210100Z
URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 236
NWS Storm Prediction Center Norman OK
350 PM EDT Wed May 20 2026
The NWS Storm Prediction Center has issued a
* Severe Thunderstorm Watch for portions of
Eastern Kentucky
Southern Ohio
Extreme Southwest Virginia
Central and Southern West Virginia
* Effective this Wednesday afternoon and evening from 350 PM
until 900 PM EDT.
* Primary threats include...
Scattered damaging wind gusts to 70 mph possible
Scattered large hail events to 1 inch in diameter possible
SUMMARY...Thunderstorms over Kentucky will track eastward in a
warm/unstable air mass, with the strongest storms posing some risk
of damaging wind gusts through the afternoon/evening.
The severe thunderstorm watch area is approximately along and 45
statute miles north and south of a line from 30 miles southwest of
Jackson KY to 15 miles east northeast of Elkins WV. For a complete
depiction of the watch see the associated watch outline update
(WOUS64 KWNS WOU6).
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 234...WW 235...
AVIATION...A few severe thunderstorms with hail surface and aloft to
1 inch. Extreme turbulence and surface wind gusts to 60 knots. A few
cumulonimbi with maximum tops to 500. Mean storm motion vector
27030.
...Hart
Read more
WW 235 SEVERE TSTM CT DE MD NJ NY PA CW 201805Z - 210100Z
URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 235
NWS Storm Prediction Center Norman OK
205 PM EDT Wed May 20 2026
The NWS Storm Prediction Center has issued a
* Severe Thunderstorm Watch for portions of
Southern Connecticut
Delaware
Eastern Maryland
New Jersey
Southeast New York
Eastern Pennsylvania
Coastal Waters
* Effective this Wednesday afternoon and evening from 205 PM
until 900 PM EDT.
* Primary threats include...
Scattered damaging wind gusts to 70 mph likely
Isolated large hail events to 1 inch in diameter possible
SUMMARY...Scattered thunderstorms will develop and track eastward
across the watch area through the afternoon and evening. Hot and
unstable conditions will lead to conditions supportive of damaging
wind gusts in the strongest storms.
The severe thunderstorm watch area is approximately along and 55
statute miles north and south of a line from 35 miles northwest of
Wilmington DE to 25 miles southeast of Groton CT. 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 234...
AVIATION...A few severe thunderstorms with hail surface and aloft to
1 inch. Extreme turbulence and surface wind gusts to 60 knots. A few
cumulonimbi with maximum tops to 500. Mean storm motion vector
27030.
...Hart
Read more
WW 234 SEVERE TSTM DC MD PA VA WV CW 201640Z - 210000Z
URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 234
NWS Storm Prediction Center Norman OK
1240 PM EDT Wed May 20 2026
The NWS Storm Prediction Center has issued a
* Severe Thunderstorm Watch for portions of
District Of Columbia
Maryland
Southern Pennsylvania
Northern Virginia
Eastern Panhandle of West Virginia
Coastal Waters
* Effective this Wednesday afternoon and evening from 1240 PM
until 800 PM EDT.
* Primary threats include...
Scattered damaging wind gusts to 70 mph likely
Isolated large hail events to 1 inch in diameter possible
SUMMARY...Thunderstorms will form and spread eastward across the
watch area this afternoon in a hot and unstable air mass. The
strongest cells will pose a risk of damaging wind gusts and hail.
The severe thunderstorm watch area is approximately along and 55
statute miles north and south of a line from 95 miles west southwest
of Martinsburg WV to 45 miles east of Harrisburg PA. For a complete
depiction of the watch see the associated watch outline update
(WOUS64 KWNS WOU4).
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 inch. Extreme turbulence and surface wind gusts to 60 knots. A few
cumulonimbi with maximum tops to 500. Mean storm motion vector
26030.
...Hart
Read more
WW 0237 Status Updates
STATUS REPORT ON WW 237
THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA.
..KERR..05/20/26
ATTN...WFO...MAF...
STATUS REPORT FOR WS 237
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
TXC043-243-371-377-443-202240-
TX
. TEXAS COUNTIES INCLUDED ARE
BREWSTER JEFF DAVIS PECOS
PRESIDIO TERRELL
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
CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES.
Read more
WW 0236 Status Updates
STATUS REPORT ON WW 236
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 20 W HTS TO
25 NNW CRW TO 20 SW PKB.
..CHALMERS..05/20/26
ATTN...WFO...JKL...RLX...
STATUS REPORT FOR WS 236
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
KYC013-025-051-071-095-115-119-121-127-131-133-153-159-193-195-
202140-
KY
. KENTUCKY COUNTIES INCLUDED ARE
BELL BREATHITT CLAY
FLOYD HARLAN JOHNSON
KNOTT KNOX LAWRENCE
LESLIE LETCHER MAGOFFIN
MARTIN PERRY PIKE
VAC027-051-202140-
VA
. VIRGINIA COUNTIES INCLUDED ARE
BUCHANAN DICKENSON
WVC005-007-011-013-015-019-021-035-039-041-043-045-047-059-067-
075-079-081-083-087-097-099-101-105-109-202140-
WV
Read more
WW 0235 Status Updates
STATUS REPORT ON WW 235
THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA.
..CHALMERS..05/20/26
ATTN...WFO...OKX...PHI...
STATUS REPORT FOR WS 235
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
CTC001-007-009-011-202140-
CT
. CONNECTICUT COUNTIES INCLUDED ARE
FAIRFIELD MIDDLESEX NEW HAVEN
NEW LONDON
DEC001-003-005-202140-
DE
. DELAWARE COUNTIES INCLUDED ARE
KENT NEW CASTLE SUSSEX
MDC011-029-035-041-202140-
MD
. MARYLAND COUNTIES INCLUDED ARE
CAROLINE KENT QUEEN ANNE'S
TALBOT
Read more
WW 0234 Status Updates
STATUS REPORT ON WW 234
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 10 E EKN TO
35 E EKN TO 45 SW MRB TO 25 SSW MRB TO 10 ESE HGR TO 20 S CXY TO
20 W AVP.
..CHALMERS..05/20/26
ATTN...WFO...LWX...CTP...
STATUS REPORT FOR WS 234
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
DCC001-202140-
DC
. DISTRICT OF COLUMBIA COUNTIES INCLUDED ARE
DISTRICT OF COLUMBIA
MDC003-005-013-015-021-025-027-031-033-510-202140-
MD
. MARYLAND COUNTIES INCLUDED ARE
ANNE ARUNDEL BALTIMORE CARROLL
CECIL FREDERICK HARFORD
HOWARD MONTGOMERY PRINCE GEORGES
MARYLAND INDEPENDENT CITIES INCLUDED ARE
BALTIMORE CITY
Read more
MD 0808 CONCERNING SEVERE THUNDERSTORM WATCH 235... FOR PORTIONS OF SOUTHWESTERN CONNECTICUT INTO EXTREME SOUTHEAST NEW YORK...NEW JERSEY...MUCH OF DELAWARE...EXTREME EASTERN MARYLAND
Mesoscale Discussion 0808
NWS Storm Prediction Center Norman OK
0429 PM CDT Wed May 20 2026
Areas affected...portions of southwestern Connecticut into extreme
southeast New York...New Jersey...much of Delaware...extreme eastern
Maryland
Concerning...Severe Thunderstorm Watch 235...
Valid 202129Z - 202230Z
The severe weather threat for Severe Thunderstorm Watch 235
continues.
SUMMARY...Damaging to severe gusts remain a concern across portions
of the Mid-Atlantic. The best chance for a severe gust exists with
the north-to-south oriented portion of the line.
DISCUSSION...Multicellular convection has loosely organized into a
progressive MCS across portions of the Mid Atlantic. In the last few
hours, several damaging gusts have been received. Preceding the
storms is a well-mixed boundary layer, characterized by over 1500
J/kg MLCAPE due to 8-9 C/km 0-3 km lapse rates overlapping 90+ F
surface temperatures. Furthermore, vertical speed shear, while
moderate (e.g. 25 kts per 21Z mesoanalysis), is oriented roughly
normal to the MCS leading line. As such, damaging gusts are expected
to continue for a few more hours. The best chance for damaging gusts
will be with the northern portions of the MCS (from PHL to areas
west of NYC) given the most favorable alignment with the deep-layer
shear vector.
..Squitieri.. 05/20/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...OKX...ALY...PHI...AKQ...LWX...
LAT...LON 38787625 39717555 40697500 41227442 41497347 41457258
41317221 41147212 40827296 40587353 39877404 39347443
38857504 38687542 38617575 38787625
MOST PROBABLE PEAK WIND GUST...55-70 MPH
MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN
Read more
MD 0807 CONCERNING SEVERE THUNDERSTORM WATCH 236... FOR PORTIONS OF EASTERN KENTUCKY INTO CENTRAL WEST VIRGINIA
Mesoscale Discussion 0807
NWS Storm Prediction Center Norman OK
0355 PM CDT Wed May 20 2026
Areas affected...portions of eastern Kentucky into central West
Virginia
Concerning...Severe Thunderstorm Watch 236...
Valid 202055Z - 202230Z
The severe weather threat for Severe Thunderstorm Watch 236
continues.
SUMMARY...The threat for damaging wind gusts continues across Severe
Thunderstorm Watch 236.
DISCUSSION...Latest radar imagery depicts several ongoing
thunderstorm clusters from southern Kentucky northeastward into
western/central West Virginia, with a couple of recent 1" hail
reports noted north of Charleston, West Virginia. Continued diurnal
heating has supported temperatures warming well into the 80s F
across the region, which is subsequently contributing to 1000-1500
J/kg MLCAPE. Steep low-level lapse rates (exceeding 8 C/km per
latest objective analysis) and dewpoint depressions of 20-25 F
evident in recent surface observations continue to promote at least
some potential for damaging wind gusts with ongoing thunderstorms.
Modest effective shear (generally less than 30 kts) and weak
mid-level lapse rates will largely temper the threat for large hail,
but isolated small to marginally severe hail remains possible with
the most robust cores. Expectation is for ongoing storms to persist
into this evening before gradually dissipating owing to low-level
nocturnal cooling/stabilization.
..Chalmers.. 05/20/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...RNK...RLX...MRX...JKL...
LAT...LON 36968281 36698350 36698380 36948391 37278383 37618341
38018272 38448196 38548165 38598115 38548078 38368061
38198061 37888088 37728114 37278204 36968281
MOST PROBABLE PEAK WIND GUST...55-70 MPH
MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN
Read more
SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0256 PM CDT Wed May 20 2026
Valid 202000Z - 211200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM EASTERN
KENTUCKY INTO PARTS OF THE MID-ATLANTIC AND SOUTHERN NEW
ENGLAND...AND PARTS OF SOUTHWEST TEXAS...
...SUMMARY...
Scattered severe/damaging winds and isolated hail will be possible
with thunderstorms from the central Appalachians into the
Mid-Atlantic and southern New England this afternoon and evening.
Severe thunderstorms with large hail and isolated severe gusts may
also occur today across parts of west/south-central Texas.
...20Z Update...
The forecast remains largely on track. Only minor adjustment to the
wind probabilities were made based on current observations and
recent guidance.
..Wendt.. 05/20/2026
.PREV DISCUSSION... /ISSUED 1101 AM CDT Wed May 20 2026/
...WV to Southern New England...
A broad upper ridge is present today over the southeastern U.S.,
with the southern fringe of stronger westerlies extending from the
OH Valley into the Mid-Atlantic region. Visible satellite imagery
shows a zone of relatively clear skies from KY/WV into southeast
PA/NJ and southern New England. Strong heating in this corridor
will lead to moderate CAPE by mid-afternoon. Scattered thunderstorm
development is expected, with steep low-level lapse rates and
sufficient westerly flow above the boundary-layer supporting a risk
of damaging wind gusts and some hail in the strongest
cores/clusters.
...Southwest TX...
Water vapor imagery shows a southern stream shortwave trough moving
into northwest Mexico, with large scale ascent approaching west TX.
Considerable cloud cover will persist in this region today, limiting
heating/destabilization. Easterly low-level upslope flow will aid
in the development of afternoon thunderstorms over the Davis
mountains, with storms spreading slowly eastward through the
evening. A few severe storms are possible, capable of large hail
and gusty/damaging winds.
Read more
SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1224 PM CDT Wed May 20 2026
Valid 211200Z - 221200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS EASTERN
COLORADO...
...SUMMARY...
Widely scattered severe storms are expected to develop across
eastern Colorado Thursday afternoon and evening. Large hail will be
the predominant hazard, with locally severe wind gusts and perhaps a
brief tornado or two also possible.
...Synopsis...
A short-wave trough and associated jet streak initially over the
northern Rockies Thursday morning will progress southeast into the
central Rockies by Thursday night. Farther to the south, a
short-wave trough will translate from the southern Plains into lower
MS Valley.
At the surface, a weak surface low is expected to develop from
southeast WY into western SD by Thursday evening, along a front
advancing through the northern High Plains. A lee trough will deepen
from the vicinity of low south through eastern parts of CO and NM.
Elsewhere, a cold front will push south from VA into the Carolinas
with the western extension of that boundary lifting north through
the lower MS Valley Thursday night in response to weak cyclogenesis
in that area.
...Central High Plains...
While low-level moisture will remain somewhat limited, the presence
of steep low/mid-level lapse rates will contribute to MLCAPE of
750-1000+ J/kg during the peak of the diurnal heating cycle.
Low-level upslope flow will be augmented by increased forcing for
ascent downstream from the approaching short-wave trough to foster
widely scattered thunderstorm development along favored terrain by
mid to late afternoon.
Strengthening mid-level flow coupled with the southeasterly
low-level wind component will yield effective bulk shear of 40-50
kt, supportive of supercell storm modes with the predominant hazard
being large hail. A brief tornado or two is possible, owing to
strengthening low-level shear by early evening. however, the
marginal moisture content is expected to limit a more robust threat.
...Western Dakotas...
At least a marginally unstable air mass is expected to develop ahead
of the front, supporting widely scattered thunderstorm development
by afternoon. Stronger vertical shear is expected to reside to the
south of the area, limiting the potential for organized storm modes.
Nonetheless, locally strong wind gusts and sub-severe hail appear
possible with the strongest storms.
...West Texas...
There is some model signal that a broken band of thunderstorms may
evolve near the NM/TX state line by late afternoon or evening,
amidst a steep lapse rate environment. Some potential will exist for
locally strong wind gusts and/or hail with that activity.
...Eastern Oklahoma into Northeast Texas...
The 12z convection-allowing models indicate a broader-scale complex
of storms evolving across the area Thursday. Weak vertical shear and
poor lapses are expected to limit the potential for storm
organization. However, the presence of a moist and moderately
unstable air mass will support briefly vigorous up/downdrafts
capable of locally strong wind gusts.
...Deep South Texas...
Remnants of overnight storms may be ongoing Thursday morning with
another round of thunderstorms potentially moving through the area
late Thursday night into Friday morning. Some potential will exist
for a few strong storms capable of gusty winds and hail.
...Lower MS Valley...
The models suggest that low-level shear will strengthen late
Thursday night into Friday morning in response to weak cyclogenesis
over the area. Lapse rates will be poor, limiting instability.
However, given the presence of a moist/low-lcl boundary layer, some
potential for low-level updraft rotation will exist with any deeper
convective elements, with a non-zero risk for a brief tornado.
...Southern VA into the Carolinas....
A hot, well-mixed boundary layer is forecast ahead of the front
Thursday afternoon. However, forecast soundings indicate warm
mid-level temperatures (500 mb and above), which are expected to
limit overall parcel buoyancy. Nonetheless, a few locally strong
wind gusts appear possible with storms developing along and ahead of
the boundary.
..Mead.. 05/20/2026
Read more
SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0224 PM CDT Wed May 20 2026
Valid 221200Z - 231200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE SOUTHERN PLAINS...
...SUMMARY...
Scattered strong to severe storms will be possible across portions
of the southern Plains with potential for large hail and damaging
wind.
...Synopsis...
A short-wave trough initially over the northern and central High
Plains Friday morning is expected to become negatively tilted as it
translates into the upper MS Valley Friday night. A belt of enhanced
mid/upper-level flow will accompany that feature across the central
Plains. A separate, weaker disturbance is expected to be loosely
phased with the north-central U.S. system, tracking from the Ozark
Plateau and lower MS Valley into the OH and TN Valleys.
At the surface, A cold front associated with the former disturbance
mentioned above is forecast to move through the northern and central
Plains with the trailing extension of that boundary pushing into the
southern High Plains, where it will link with a surface low. Farther
east, a secondary surface low (tied to the lower-latitude impulse)
is expected to develop from the lower MS into OH Valley with an
associated warm front lifting north through the TN into OH Valley.
...Southern Plains...
Despite rising mid-level heights through the day, convergence along
the front and/or upslope flow in its immediate wake are expected to
support widely scattered thunderstorm development over parts of
northeast/east-central NM into the TX Panhandle by mid to late
afternoon. The combination of steep low/mid-level lapse rates and
boundary-layer dewpoints in the 50s to low 60s will support a
moderately unstable air mass amidst a kinematic environment
featuring a vertically veering wind profile with effective bulk
shear of 30-35 kt. That parameter space will support organized
multicell or supercell storm modes initially with the predominant
hazard being large hail. The 12z models suggest upscale growth of
the initial storms into an MCS with an isolated hail and wind threat
continuing east across parts of OK and northwest TX Friday evening
into Friday night.
...Central Plains...
An axis of 50s to low 60s dewpoints are expected to spread north
from KS into eastern NE ahead of the cold front. However, widespread
clouds and areas of precipitation are expected to limit
boundary-layer heating and air mass destabilization. So, despite
increased forcing for ascent and strengthening low-level and
deep-layer shear, the unfavorable thermodynamic environment is
expected to preclude severe-storm potential.
...TN and OH Valleys...
Numerous showers and thunderstorms are expected through the forecast
period along and south of the warm front, aiding by forcing for
ascent associated with the short-wave trough moving through the
region. Generally weak lapse rates are expected to limit air mass
destabilization, despite the presence of boundary-layer dewpoints in
the 60s to low 70s. However, a modest enhancement of mid-level winds
attending the short-wave trough, and more so, intensifying 850-mb
flow Friday afternoon into night, will result in strengthening
vertical shear, especially across the OH Valley Friday night. As
such, potential will exist for transient supercell structures to be
embedded in the broader-scale convective shield with a non-zero risk
for a brief tornado.
..Mead.. 05/20/2026
Read more
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0156 PM CDT Wed May 20 2026
Valid 211200Z - 221200Z
...NO CRITICAL AREAS...
...Afternoon Update...
As the mid-level shortwave trough traverses the northern Rockies, a
southward progressing cold front will push through the Great Basin
and upper Southwest on Day 2/Thursday. Ahead of the cold front,
localized terrain-enhanced southwesterly winds will increase to
10-20 mph as RH declines to 10-20% at peak heating. A narrow region
of stronger west-southwesterly winds (15-25 mph) will develop across
eastern UT and western CO, though displaced from the lowest RH,
prior to the cold front arrival. As the front passes in the evening,
briefly gusty northerly winds and increased surface moisture will
envelop the region. The more localized nature of elevated fire
weather conditions and sparsely continuous fuels precludes the
introduction of highlights.
..Elizalde-Garcia.. 05/20/2026
.PREV DISCUSSION... /ISSUED 1251 AM CDT Wed May 20 2026/
...Synopsis...
On Day 2/Thursday, a shortwave trough and associated mid-level jet
streak will transit through the Intermountain West. There is some
uncertainty given trends in the recent forecast guidance as to how
far south this feature will dig and the timing of when it will
progress over the central/southern Rockies. A cold front will
continue to progress south/eastward over the Eastern Seaboard.
...Southwest...
Conditions on Day 2/Thursday will be somewhat similar to Day
1/Wednesday with southwesterly surface winds of 10-20 mph and brief
afternoon RHs of 10-20%. Given the uncertainty associated with the
aforementioned shortwave trough, marginally elevated conditions
outside of a synoptically-supported fire weather environment, and
more sparsely continuous fuels, no highlighted areas were introduced
with this forecast issuance.
...Maine...
One location that will miss out on much of any accumulating
precipitation with the aforementioned cold front passage is the
northeastern corner of the CONUS. With this offshore flow (sustained
winds of 10-15 mph) in place at the surface, RHs will also dip down
near 25-35% behind the front on Day 2/Thursday. Additionally, heavy
dead fuels will remain near the 80-90th percentile. However, well
established green up at this point will preclude any highlighted
areas.
...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
0348 PM CDT Wed May 20 2026
Valid 221200Z - 281200Z
A shortwave trough and associated mid-level jet streak will
gradually drift across the High Plains and Upper Midwest on Day
3/Friday before entering south-central Canada this weekend. On Day
4/Saturday, a weak shortwave trough over the Rockies will translate
eastward into the Great Lakes by Day 5/Sunday. Longwave ridging will
build across the West on Day 4/Saturday, sliding towards the Central
U.S. as extended guidance introduces the potential for a robust
upper trough to enter the Pacific Northwest early next week. An
Atlantic ridge over the Eastern Seaboard is likely to persist
through the forecast period, with multiple rounds of mid-level
perturbations promoting repeat opportunities for precipitation. The
upper pattern suggests dampened fire weather conditions on a broader
scale through the weekend, with the exception of localized breezy
conditions across parts of the West.
Guidance remains ambiguous in the timing and extent of the
approaching Pacific trough towards the latter half of the forecast
period. However, fire weather highlights may be warranted in future
outlooks as confidence increases in the overall pattern, and the
overlap of dry/breezy conditions atop receptive fuels is recognized.
..Elizalde-Garcia.. 05/20/2026
...Please see www.spc.noaa.gov/fire for graphic product...
Read more
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