WW 398 SEVERE TSTM CO NE NM OK TX WY 262040Z - 270300Z
URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 398
NWS Storm Prediction Center Norman OK
240 PM MDT Fri Jun 26 2026
The NWS Storm Prediction Center has issued a
* Severe Thunderstorm Watch for portions of
Eastern Colorado
Western Nebraska
Northeast New Mexico
Western Oklahoma Panhandle
Northwest Texas Panhandle
Eastern Wyoming
* Effective this Friday afternoon and evening from 240 PM until
900 PM MDT.
* Primary threats include...
Scattered large hail and isolated very large hail events to 2.5
inches in diameter possible
Scattered damaging wind gusts to 70 mph possible
A tornado or two possible
SUMMARY...At least widely scattered severe storms including a few
supercells and multicells are expected regionally, with large hail
and damaging winds the primary hazards.
The severe thunderstorm watch area is approximately along and 60
statute miles east and west of a line from 40 miles east northeast
of Douglas WY to 25 miles south of Clayton NM. For a complete
depiction of the watch see the associated watch outline update
(WOUS64 KWNS WOU8).
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 397...
AVIATION...A few severe thunderstorms with hail surface and aloft to
2.5 inches. Extreme turbulence and surface wind gusts to 60 knots. A
few cumulonimbi with maximum tops to 600. Mean storm motion vector
28025.
...Guyer
WW 397 SEVERE TSTM ME NH VT 261815Z - 270100Z
URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 397
NWS Storm Prediction Center Norman OK
215 PM EDT Fri Jun 26 2026
The NWS Storm Prediction Center has issued a
* Severe Thunderstorm Watch for portions of
Southwest Maine
New Hampshire
Vermont
* Effective this Friday afternoon and evening from 215 PM until
900 PM EDT.
* Primary threats include...
Scattered damaging wind gusts to 65 mph possible
Isolated large hail events to 1.5 inches in diameter possible
A tornado or two possible
SUMMARY...Storms should intensify initially over Vermont, with
additional development and movement east-southeastward into New
Hampshire and southwest Maine through late afternoon and early
evening, with hail and damaging winds as the primary hazards.
The severe thunderstorm watch area is approximately along and 45
statute miles north and south of a line from 25 miles northwest of
Rutland VT to 15 miles north northeast of Portsmouth NH. 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
29025.
...Guyer
WW 0398 Status Updates
STATUS FOR WATCH 0398 HAS NOT BEEN ISSUED YET
WW 0397 Status Updates
STATUS REPORT ON WW 397
THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA.
FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 1335
..MEAD..06/26/26
ATTN...WFO...GYX...BTV...
STATUS REPORT FOR WS 397
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
MEC031-262140-
ME
. MAINE COUNTIES INCLUDED ARE
YORK
NHC001-003-005-009-011-013-015-017-019-262140-
NH
. NEW HAMPSHIRE COUNTIES INCLUDED ARE
BELKNAP CARROLL CHESHIRE
GRAFTON HILLSBOROUGH MERRIMACK
ROCKINGHAM STRAFFORD SULLIVAN
VTC001-017-021-027-262140-
VT
. VERMONT COUNTIES INCLUDED ARE
ADDISON ORANGE RUTLAND
MD 1336 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR SOUTHEAST MISSOURI INTO SOUTHERN ILLINOIS AND WESTERN KENTUCKY
Mesoscale Discussion 1336
NWS Storm Prediction Center Norman OK
0336 PM CDT Fri Jun 26 2026
Areas affected...southeast Missouri into southern Illinois and
western Kentucky
Concerning...Severe potential...Watch possible
Valid 262036Z - 262230Z
Probability of Watch Issuance...60 percent
SUMMARY...The potential for a few severe storms capable of locally
damaging winds and perhaps a few tornadoes appears to be increasing.
Convective trends are being monitored for a possible watch.
DISCUSSION...A small cluster of thunderstorms has recently
intensified in the vicinity of I-55 near Cape Girardeau, on the
southwest flank of a large-scale convective system collocated with
an MCV. The ambient environment is quite moist and moderately
unstable with MLCAPE estimated in the 1000-1500 J/kg range. The
storms have exhibited some rotation amidst a modestly sheared
environment, per the current KPAH VWP. However, latest short-term
model guidance suggests that a southwesterly low-level jet will
gradually strengthen late this afternoon into early evening, which
will contribute to some increase in low-level shear. As such,
tornado potential may tend to increase over the next hour or two,
along with a risk for damaging wind gusts.
Convective trends are being monitored for a possible watch issuance.
..Mead/Guyer.. 06/26/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...PAH...LSX...
LAT...LON 37239022 37658998 37888927 37948842 37688788 37098792
36838813 36638862 36618910 36688951 36858999 37239022
MOST PROBABLE PEAK TORNADO INTENSITY...85-110 MPH
MOST PROBABLE PEAK WIND GUST...55-70 MPH
MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN
MD 1335 CONCERNING SEVERE THUNDERSTORM WATCH 397... FOR PORTIONS OF CENTRAL AND SOUTHERN VERMONT AND NEW HAMPSHIRE TO THE SOUTH COAST OF MAINE.
Mesoscale Discussion 1335
NWS Storm Prediction Center Norman OK
0316 PM CDT Fri Jun 26 2026
Areas affected...portions of central and southern Vermont and New
Hampshire to the South Coast of Maine.
Concerning...Severe Thunderstorm Watch 397...
Valid 262016Z - 262215Z
The severe weather threat for Severe Thunderstorm Watch 397
continues.
SUMMARY...The threat for large hail up to 1.5" and locally severe
wind gusts of 60-65 kt continues across the watch area.
DISCUSSION...An earlier cluster of thunderstorms with embedded
supercell structures that produced wind damage and some small hail
in central Rutland County, VT has recently weakened. However, the
lingering convection is in the vicinity of a diffuse warm front that
extends southeast through southeastern NH. That boundary along with
orographic ascent along favored terrain in the Green and White
Mountains may aid in additional storm formation late this afternoon
into early evening. Given the presence of 1000 J/kg MLCAPE and 35-45
kt of effective bulk shear, the environment is expected to remain
supportive of additional severe storms capable of hail up to 1.5"
and damaging wind gusts for the next few hours.
..Mead.. 06/26/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...GYX...BTV...ALY...
LAT...LON 44067338 44247302 44267191 44117134 43787089 43477061
43047090 42847146 42867212 43007255 43407321 44067338
MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 90 MPH
MOST PROBABLE PEAK WIND GUST...55-70 MPH
MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN
MD 1334 CONCERNING SEVERE POTENTIAL...WATCH LIKELY FOR PORTIONS OF NORTHEASTERN COLORADO...SOUTHEASTERN WYOMING...AND FAR WESTERN NEBRASKA
Mesoscale Discussion 1334
NWS Storm Prediction Center Norman OK
0313 PM CDT Fri Jun 26 2026
Areas affected...portions of northeastern Colorado...southeastern
Wyoming...and far western Nebraska
Concerning...Severe potential...Watch likely
Valid 262013Z - 262115Z
Probability of Watch Issuance...80 percent
SUMMARY...A few thunderstorms with large hail and severe gusts are
possible this afternoon across portions of northeastern Colorado,
southeastern Wyoming, and far western Nebraska. A watch may be
needed to cover this threat.
DISCUSSION...A large upper trough is in place across the
northwestern CONUS with a subtle jet pushing eastward over the
central Rockies this afternoon. Storms are preferentially developing
along a couple convergence boundaries across portions of the High
Plains. The flow enhancement from the jet results in lengthened
hodographs, which should result in enough shear for at least a few
supercells.
With any supercells that do form, a few instances of large hail are
possible due to the straight hodographs and relatively low freezing
levels. Storms may cluster as the afternoon progresses, which may
result in a threat for severe gusts due to the dry boundary layer
and modest low- and mid-level flow. One limiting factor for wind is
some residual inhibition across parts of the High Plains, though
this is expected to erode with continued strong heating. A watch
will likely be needed to cover this threat.
..Supinie/Guyer.. 06/26/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...GLD...PUB...BOU...CYS...
LAT...LON 40180486 41600487 42170478 42370419 42060336 40850299
39610286 38200360 38100442 38410473 40180486
MOST PROBABLE PEAK WIND GUST...55-70 MPH
MOST PROBABLE PEAK HAIL SIZE...1.50-2.50 IN
MD 1333 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR CENTRAL VIRGINIA INTO THE DELMARVA
Mesoscale Discussion 1333
NWS Storm Prediction Center Norman OK
0237 PM CDT Fri Jun 26 2026
Areas affected...central Virginia into the Delmarva
Concerning...Severe potential...Watch unlikely
Valid 261937Z - 262130Z
Probability of Watch Issuance...20 percent
SUMMARY...The potential for locally damaging wind gusts is expected
to increase across the discussion area this afternoon into early
evening. The areal coverage and magnitude of the threat are expected
to remain too limited for a watch consideration.
DISCUSSION...Recent radar trends indicate gradually strengthening
storms along the Blue Ridge Mountains in northern VA with additional
storms noted in southeast WV. East of the high terrain, a relatively
warm and moist air mass is present with steep low-level lapse rates
and MLCAPE of around 1000 J/kg indicated in latest objective
analyses. The presence of a westerly, deep-layer wind field should
support the eastward movement of storms across the discussion area
with the absence of appreciable forcing for ascent potentially
limiting overall storm coverage.
The KRLX and KLWX VWPs indicate 30-35 kt winds above 5 km, which are
boosting vertical shear generally along and north of that latitude.
That modest shear enhancement may contribute to some briefly
organized storms capable of locally damaging wind gusts. Relatively
warm mid-level temperatures and resultant poor lapse rates should
limit large hail potential.
Given the expected isolated nature of the threat, a watch is not
anticipated.
..Mead/Guyer.. 06/26/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...PHI...AKQ...LWX...RNK...
LAT...LON 37917993 38317971 38907858 39347734 39357633 39097564
38577537 37957594 37637758 37397828 37357879 37407922
37537966 37917993
MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH
MD 1332 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PORTIONS OF THE COASTAL CAROLINAS
Mesoscale Discussion 1332
NWS Storm Prediction Center Norman OK
0158 PM CDT Fri Jun 26 2026
Areas affected...portions of the coastal Carolinas
Concerning...Severe potential...Watch unlikely
Valid 261858Z - 262130Z
Probability of Watch Issuance...20 percent
SUMMARY...A damaging gust or two is possible this afternoon across
portions of the coastal Carolinas. A watch is not anticipated.
DISCUSSION...A seasonably moist air mass is in place across portions
of the eastern Carolinas, where convective temperatures have been
reached, resulting in scattered thunderstorms ongoing this
afternoon. The KLTX VWP shows generally weak flow, which correlates
with the single- and multicell modes apparent on radar. Due to the
high precipitable water values (>2 in) in place across the region,
water loading in downdrafts may be enough for some damaging gusts
across the region. Additionally, storms may cluster with time, and
this may slightly increase the threat for damaging gusts. However,
this threat is still expected to be fairly sporadic, and therefore a
watch is not expected at this time.
..Supinie/Guyer.. 06/26/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...MHX...RAH...ILM...CHS...CAE...
LAT...LON 34318072 35637883 35877771 35687717 35077709 34207802
33227910 33058014 33088070 33348119 33948112 34318072
MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1147 AM CDT Fri Jun 26 2026
Valid 261630Z - 271200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE HIGH
PLAINS TO OZARKS AND LOWER OHIO VALLEY...AS WELL AS PARTS OF NEW
ENGLAND...
...SUMMARY...
Scattered severe thunderstorm development is expected today,
particularly this afternoon into tonight across parts of the Ozark
Plateau to Lower Ohio Valley and across parts of the northern and
central High Plains to the Black Hills vicinity. Other severe storms
are expected across portions of New England.
...Ozarks and Lower Ohio Valley...
Multiple eastward-moving MCVs remain evident regionally in
observational data at midday, probably strongest across southeast
Missouri, but also the Oklahoma/Arkansas border vicinity and
northern Kentucky. A related observed enhancement to the
low/mid-level flow will persists from the Ozarks/Bootheel
east-northeastward parallel to the Ohio River, but cloud
cover/scattered precipitation remains fairly prevalent regionally as
well. Peripheral cloud breaks and insolation should allow for
gradual destabilization, particularly on the south/southwest fringes
of this early day activity. This should lead to severe storm
development into mid/late afternoon through the evening, potentially
including supercells given the flow enhancement. A couple of
tornadoes could occur aside from wind damage.
...High Plains...
A seasonably anomalous upper trough will continue to amplify and
spread eastward over the Pacific Northwest toward the Great Basin
and Intermountain West, with a lead disturbance ejecting
northeastward toward the northern High Plains. Pronounced lee
troughing is forecast with a surface low expected to evolve over
central and southeast Montana through tonight. A corridor of at
least weak to moderate boundary-layer destabilization is expected
across the High Plains. Strengthening large-scale ascent and ample
vertical shear downstream of the digging large-scale troughing will
favor organized severe thunderstorm development late this afternoon
through evening. Supercells and evolving organized clusters will
pose a risk for large hail and severe gusts, and perhaps a tornado.
Across the central into southern High Plains, isolated to widely
scattered storms will likely develop/mature and propagate east
during the evening. Hail and wind are the primary hazards with this
activity and this severe risk will probably linger into the late
evening.
...New England...
Have introduced a Slight Risk for portions of the region, primarily
focused near the advancing surface low/warm front. A shortwave
trough over Ontario/Lower Great Lakes will move east across New
England by this evening. Cloud cover, albeit abating this afternoon,
will limit the overall magnitude of destabilization, but upwards of
1000-1500 J/kg SBCAPE are forecast to develop along/south of a warm
front. Elongated hodographs beneath a 100+ kt 250-mb speed max will
aid in storm organization in the form of possibly a couple of
supercells and organized multicells. Isolated coverage of large hail
and damaging gusts are the primary risks with the stronger
thunderstorms, but the moist environment and low-level shear/SRH
could yield a tornado threat.
...Mid-Atlantic States to Carolinas...
The southern periphery of stronger mid to high-level westerly flow
is forecast across the region, atop northward-shifting low-level
moisture that is richest across the Carolinas into southern
Virginia, where near/above 70 F surface dewpoints are prevalent. The
overlap of moderate westerly flow and weak destabilization is
expected to support scattered thunderstorms capable of strong to
locally severe/damaging gusts (50-60 mph). Additional sea-breeze
influenced locally severe storms may occur across the coastal plain
of the Carolinas.
..Guyer/Supinie.. 06/26/2026
SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0300 PM CDT Fri Jun 26 2026
Valid 262000Z - 271200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE
NORTHERN/CENTRAL HIGH PLAINS...SOUTHERN PLAINS TO THE LOWER OHIO
VALLEY...AND PARTS OF NEW ENGLAND...
...SUMMARY...
Scattered severe thunderstorm development is expected today,
particularly this afternoon into tonight across parts of the
southern Plains to Lower Ohio Valley and across parts of the
northern and central High Plains to the Black Hills vicinity. Other
severe storms are expected across portions of New England.
...20Z Update...
The forecast remains on track, and only minor changes were made with
this update.
The SLGT risk in the central High Plains was expanded southeastward
from southeast CO into southwest KS and parts of the OK/TX
Panhandles. Guidance is in relatively good agreement, depicting
thunderstorms evolving off the Raton Mesa and tracking
east-southeastward along a gradient of rich boundary-layer
moisture/moderate surface-based buoyancy this evening/tonight. Aided
by 40 kt of effective shear and increasing low-level hodograph
curvature amid a strengthening nocturnal LLJ, supercell clusters
will pose a risk for severe gusts, large hail, and possibly a
tornado.
Farther east, a minor westward expansion of the SLGT risk was made
into north-central OK. Ample diurnal heating/destabilization of a
very moist air mas (middle/upper 70s dewpoints) is yielding strong
surface-based buoyancy along an east/west-oriented surface boundary.
Current thinking is that a few organized clusters/supercells
developing along the boundary will be capable of producing severe
wind gusts and large hail later this afternoon/evening.
..Weinman.. 06/26/2026
.PREV DISCUSSION... /ISSUED 1147 AM CDT Fri Jun 26 2026/
...Ozarks and Lower Ohio Valley...
Multiple eastward-moving MCVs remain evident regionally in
observational data at midday, probably strongest across southeast
Missouri, but also the Oklahoma/Arkansas border vicinity and
northern Kentucky. A related observed enhancement to the
low/mid-level flow will persists from the Ozarks/Bootheel
east-northeastward parallel to the Ohio River, but cloud
cover/scattered precipitation remains fairly prevalent regionally as
well. Peripheral cloud breaks and insolation should allow for
gradual destabilization, particularly on the south/southwest fringes
of this early day activity. This should lead to severe storm
development into mid/late afternoon through the evening, potentially
including supercells given the flow enhancement. A couple of
tornadoes could occur aside from wind damage.
...High Plains...
A seasonably anomalous upper trough will continue to amplify and
spread eastward over the Pacific Northwest toward the Great Basin
and Intermountain West, with a lead disturbance ejecting
northeastward toward the northern High Plains. Pronounced lee
troughing is forecast with a surface low expected to evolve over
central and southeast Montana through tonight. A corridor of at
least weak to moderate boundary-layer destabilization is expected
across the High Plains. Strengthening large-scale ascent and ample
vertical shear downstream of the digging large-scale troughing will
favor organized severe thunderstorm development late this afternoon
through evening. Supercells and evolving organized clusters will
pose a risk for large hail and severe gusts, and perhaps a tornado.
Across the central into southern High Plains, isolated to widely
scattered storms will likely develop/mature and propagate east
during the evening. Hail and wind are the primary hazards with this
activity and this severe risk will probably linger into the late
evening.
...New England...
Have introduced a Slight Risk for portions of the region, primarily
focused near the advancing surface low/warm front. A shortwave
trough over Ontario/Lower Great Lakes will move east across New
England by this evening. Cloud cover, albeit abating this afternoon,
will limit the overall magnitude of destabilization, but upwards of
1000-1500 J/kg SBCAPE are forecast to develop along/south of a warm
front. Elongated hodographs beneath a 100+ kt 250-mb speed max will
aid in storm organization in the form of possibly a couple of
supercells and organized multicells. Isolated coverage of large hail
and damaging gusts are the primary risks with the stronger
thunderstorms, but the moist environment and low-level shear/SRH
could yield a tornado threat.
...Mid-Atlantic States to Carolinas...
The southern periphery of stronger mid to high-level westerly flow
is forecast across the region, atop northward-shifting low-level
moisture that is richest across the Carolinas into southern
Virginia, where near/above 70 F surface dewpoints are prevalent. The
overlap of moderate westerly flow and weak destabilization is
expected to support scattered thunderstorms capable of strong to
locally severe/damaging gusts (50-60 mph). Additional sea-breeze
influenced locally severe storms may occur across the coastal plain
of the Carolinas.
SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1242 PM CDT Fri Jun 26 2026
Valid 271200Z - 281200Z
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
OF THE NORTHERN HIGH PLAINS...
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS SOUTHEAST
VA AND EASTERN NC...
...SUMMARY...
Severe storms are likely across portions of eastern Montana and
western/central North Dakota on Saturday. Severe storms will also be
possible from the Mid-Mississippi Valley to Virginia and the
Carolinas, as well as portions of the southern High Plains.
...Synopsis...
An upper low and attendant large-scale upper trough will persist
across the western U.S. on Saturday. Further east, upper ridging
over the Plains is forecast to shift east toward the Upper Midwest
and Mid-MS Valley by Sunday morning. Quasi-zonal/weak upper
troughing is expected to persist across the eastern U.S. Within this
large-scale regime, several shortwave impulses and embedded MCVs are
expected to drive severe thunderstorm potential across multiple
areas on Saturday. A lead upper shortwave trough is expected to
eject from the eastern Great Basin through the northern High Plains.
A series of MCVs will move from the Ozark Plateau to the OH/TN
Valleys, while another MCV and/or surface trough impacts
thunderstorm potential across the Mid-Atlantic/Piedmont. Finally,
another upper shortwave impulse could emerge across the central
Plains into the Mid-MO/Mid-MS Valleys.
...Northern Rockies into the Northern Plains...
A midlevel jet streak will overspread parts of the Great Basin into
the northern Plains, characterized by 50-60 kt southwesterly 500 mb
flow. Cooling aloft is also forecast and will result in a plume of
steep midlevel lapse rates. Surface low pressure is forecast to
deepen across northeast WY/western SD through evening. This will
support northward transport of low to mid 60s F dewpoints into
eastern MT/ND/SD. This will result in a narrow corridor of moderate
to strong instability. Capping will increase with eastward extent as
a result of midlevel height rises/warming aloft, which should
confine the eastward extent of severe potential.
As large-scale ascent increasing during the afternoon, convection is
expected to develop across the higher terrain of northern UT/ID into
WY. This initial activity will pose a risk for strong wind gusts and
isolated hail given strong deep-layer flow, steep midlevel lapse
rates, and a well mixed boundary layer. Additional convection is
expected to develop near the Big Horns and Beartooth/Absaroka
ranges. As this activity develops northeast into better low-level
moisture and strong instability, large to very large hail potential
will increase. With time during the evening, a southerly low-level
jet will increase across the Dakotas. Upscale growth is possible as
convection moves toward the terminus of the low-level jet and as
sufficient clustering/cold pool development occurs. If this
convective evolution unfolds, a swath of damaging wind gusts will be
possible, mainly across eastern MT into western ND.
...Mid-Atlantic...
Ongoing convection and cloudiness will likely hinder daytime
destabilization. Nevertheless, several shortwave impulses will move
across the region along with 25-30 kt westerly midlevel flow.
Isolated strong storms may produce gusty winds. The Slight risk
(level 2 of 5) has been confined to areas nearer the coast where
instability will be greatest.
...Southern High Plains...
A surface trough/dryline will extend south/southwest from western KS
to southwest TX. A moist airmass will exist east of this boundary
with hot temperatures forecast along and just behind the boundary.
Moderate to strong destabilization will occur near the boundary in a
narrow corridor, confined by stronger capping to the east across
much of OK/KS/central TX. However, isolated to widely scattered
storms are expected to develop during peak heating to early evening.
Vertically veering wind profiles with up to 25 kt effective shear
magnitudes suggest organized updrafts and high-based transient
supercell structures are possible. Given a deeply mixed boundary
layer, strong gusts will be possible. Organized updrafts that can be
maintained also will pose a risk of large hail given very steep
midlevel lapse rates and somewhat elongated hodographs.
...Ozarks to TN Valley vicinity...
Storms are forecast to be ongoing Saturday morning across southwest
MO. This activity could pose a marginal wind/hail risk initially.
Additional development is expected from southern IL/southeast MO
into KY/TN by late morning and spread east through the afternoon as
an MCV moves across the region. While deep layer flow will not be
impressive, the MCV could locally enhanced vertical shear.
Thunderstorm clusters will mainly pose a risk for damaging winds as
they track across moisture-rich and moderately unstable airmass.
...Northeast CO/Western NE into central SD...
Convection may develop during the late afternoon along the surface
trough/dryline. Rich boundary layer moisture beneath steep lapse
rates will support strong destabilization. This corridor will remain
rather confined given rising midlevel heights and capping to the
east. Any storms that develop will have potential for strong outflow
gusts and large hail.
...Mid-MO Valley vicinity...
It is uncertain if convection will develop across this area, or if
it does - will it be surface-based, resulting in a rather
conditional severe risk. If storms can develop, an all-hazards
severe risk would be possible given a surface warm front lifting
north across the region amid ample moisture/instability and
supercell wind profiles. Given the conditional nature of the risk,
particularly due to capping, will maintain low severe probabilities.
..Leitman.. 06/26/2026
SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0216 PM CDT Fri Jun 26 2026
Valid 281200Z - 291200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF
NORTH DAKOTA AND THE UPPER MIDWEST...
...SUMMARY...
Severe thunderstorms are possible from the northern Plains into
parts of the Upper Midwest on Sunday. Large hail and severe winds
are the primary hazards.
...Synopsis...
The western U.S. upper trough will deepen and persist over that
region on Sunday. Meanwhile, upper ridging will intensify over the
Midwest into the South, while a shortwave upper trough moves from
the Ohio Valley to the southern Mid-Atlantic region. At the surface,
some uncertainty persists with regards to the location of lee
surface low development in the central or northern Plains. The NAM
appears to be an outlier compared to the ECMWF/GFS and the AI
versions thereof. This will be important for where the best corridor
of severe thunderstorm potential develops on Sunday
afternoon/evening. Further east, a surface front will sag southward
across the Upper OH Valley and portions of the Mid-Atlantic. Between
these surface boundaries, a seasonally very moist airmass will exist
across at least eastern portions of the Plains to the MS Valley and
the southern Mid-Atlantic.
...Northern Plains/Upper Midwest vicinity...
The forecast for Sunday is highly uncertain. Forecast guidance
suggests a shortwave impulse and/or MCV will move across northern MN
during the afternoon/evening. This area will be beneath the upper
ridge axis and could be capped. However, a very moist airmass will
be in place beneath steep midlevel lapse rates. Furthermore, a
strong southerly low-level jet is expected to focus from the central
Plains to the Upper MS Valley during the evening/nighttime hours. If
storms can develop and become near-surface based, potential for
damaging wind gusts and large hail will be possible. This scenario
is generally supported by the RRFS and GSL MPAS, though
location/timing varies.
Forecast guidance develops additional areas of convection across
portions of western NE/central SD into ND on the western periphery
of stronger capping and near the surface trough/dryline within the
gradient of stronger instability. This scenario is uncertain, both
regarding storm development, and if storms occur, whether or not
they will be surface-based. However, if storms do develop, an
intense low-level jet within the strongly unstable airmass during
the evening/overnight hours could support damaging wind potential.
The Marginal risk (level 1 of 5) has been adjusted to reflect this
conditional risk.
...Southern Mid-Atlantic...
Forecast guidance suggests an MCV will move across the central
Appalachians into parts of VA/NC on Sunday. Deep-layer flow is not
expected to be particularly strong, but this feature could locally
enhanced vertical shear, with some guidance showing effective shear
magnitudes up to 25 kt are possible. A seasonally very moist airmass
will reside east of the higher terrain across southeast VA into the
eastern Carolinas, supporting moderate destabilization as strong
daytime heating occurs. Thunderstorms will pose an isolated damaging
wind risk into early evening.
..Leitman.. 06/26/2026
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1151 AM CDT Fri Jun 26 2026
Valid 261700Z - 271200Z
...EXTREMELY CRITICAL FIRE WEATHER AREA FOR CENTRAL UTAH INTO
NORTHWESTERN ARIZONA AND EXTREME SOUTHEASTERN NEVADA...
...CRITICAL FIRE WEATHER AREA FOR MUCH OF UTAH...EASTERN
NEVADA...NORTHERN ARIZONA...SOUTHWESTERN WYOMING...AND FAR WESTERN
COLORADO...
***Dangerous fire weather conditions are expected today across
portions of the Great Basin and Southwest***
...Northwestern Arizona and far southeastern Nevada into central
Utah...
The forecast remains on track for hazardous weather conditions
conducive to rapid spread/fire growth on existing wildfires and new
ignitions. Surface observations already depict expansive
single-digit RH values with wind gusts exceeding 30 mph. ERCs are at
or above the 90th percentile, and fuels have proven to be receptive
as several large wildfires (reported to have extreme fire behavior)
are ongoing across the region. At peak heating, sustained
southwesterly surface winds will increase to 25-35 mph amid 5-12% RH
values. An extended burning period is expected (10+ hours for some
locations), as poor overnight humidity recoveries and residual gusty
winds will lead into a second day of dangerous fire weather
conditions (see the Day 2 Fire Weather Outlook).
See the previous discussion for more information.
..Elizalde-Garcia.. 06/26/2026
.PREV DISCUSSION... /ISSUED 0300 AM CDT Fri Jun 26 2026/
...Synopsis...
Dangerous fire weather conditions are forecast across portions of
the Great Basin and Southwest today as a robust fire weather pattern
begins for an expansive portion of the Intermountain West. This
pattern will bring exceptionally dry and windy conditions following
antecedent dry thunderstorm activity over the past 1-2 days,
resulting in significant fire weather concerns for any new
ignitions, lingering holdovers, and ongoing large fires across the
western CONUS.
...Northwestern Arizona and far southeastern Nevada into central
Utah...
A seasonably strong mid-level trough will dig into the western CONUS
today, with an attendant mid-level jet overspreading portions of the
Great Basin as upper-level ridging amplifies over the Great Plains.
This will promote a deepening surface cyclone over the northern
Great Basin, which will subsequently support a strong surface
pressure gradient across much of the Intermountain West when
combined with surface high pressure over New Mexico. Latest high-res
guidance continues to depict a corridor of strong southwesterly
winds (sustained 25-35 mph) developing amid very low RH values of
5-15% from far southeastern Nevada and northwestern Arizona into
central Utah. With very dry and receptive fuels across this region
(ERCs in the 80-90+ percentiles) and ongoing large wildfire
activity, these conditions will yield an extremely critical fire
weather threat across this region. Deep boundary layer mixing
coupled with the aforementioned mid-level jet will also promote wind
gusts to 45 mph. A more expansive area of elevated to critical fire
weather concerns is expected across adjacent areas of the Great
Basin where modestly weaker sustained surface winds (generally 15-25
mph) are forecast to overlap very low RH values of 5-20%. An
extended period of critical wind/RH conditions (perhaps 10+ hours
for some locations), poor overnight humidity recoveries, and
residual gusty winds are forecast. Only minor adjustments were made
to the drawn areas with this update to reflect the latest available
guidance, and minor trimming was done on the northeastern extent of
the Elevated highlights in central Wyoming to account for heavier
rainfall on Thursday.
...Colorado Plateau...
Increasing mid-level flow and ascent ahead of the approaching
mid-level trough (coupled with dry boundary layer profiles and PWAT
values of 0.5-0.8") will support the potential for isolated dry
thunderstorms this afternoon from northwestern New Mexico into much
of western Colorado. While storm motions are anticipated to be
generally 20-30+ kts, pockets of heavier rainfall totals are
possible, especially across northwestern New Mexico and southwestern
Colorado where the latest guidance suggests PWAT contents and storm
coverage may be locally greater. Thus, a mix of wet/dry
thunderstorms is likely. Pockets of lingering receptive fuels (ERCs
in the 80-90+ percentile) will continue to be receptive to lightning
ignitions, however, and concerns regarding any lightning ignitions
increase as multiple days of critical fire weather conditions are
expected this weekend.
...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
0230 PM CDT Fri Jun 26 2026
Valid 271200Z - 281200Z
...EXTREMELY CRITICAL FIRE WEATHER AREA FOR PORTIONS OF WESTERN
COLORADO AND EASTERN UTAH INTO THE FOUR CORNERS REGION...
...CRITICAL FIRE WEATHER AREA FOR MUCH OF NEVADA...NORTHERN
ARIZONA...NORTHWESTERN NEW MEXICO...CENTRAL/SOUTHERN UTAH...SOUTHERN
WYOMING...AND WESTERN COLORADO...
***Dangerous fire weather conditions are expected on Day 2/Saturday
across the Four Corners into portions of the Colorado Plateau***
...Afternoon Update...
An Extremely Critical risk area was introduced where guidance
depicts an overlap of sustained 25-35 mph southwesterly winds and
less than 10% RH on Day 2/Saturday. Despite some recent rainfall
across the West Slope, appreciable precipitation was not common, and
rather quite localized. Widespread 80-95th percentile ERCs and
recently receptive fuels will be conducive to rapid spread/fire
growth on existing wildfires and any new ignitions. Furthermore,
isolated dry thunderstorms on Day 1/Friday present additional
concerns for potential lightning holdovers to emerge as several days
of hot, dry and windy conditions ensue. An extended burning period
is expected (10+ hours for some locations) with poor overnight
humidity recoveries and residual gusty winds leading into another
day of critical fire weather conditions (see the Day 3-8 Fire
Weather Outlook).
The rest of the forecast remains on track, see the previous
discussion for more information.
..Elizalde-Garcia.. 06/26/2026
.PREV DISCUSSION... /ISSUED 0302 AM CDT Fri Jun 26 2026/
...Synopsis...
A seasonably strong mid-level trough will continue to dig into the
western CONUS on D2/Saturday, with an attendant mid-level jet
overspreading much of the Upper Colorado River Basin. This will
continue to support a robust fire weather pattern across an
expansive portion of the Great Basin and Southwest through the
weekend.
...Great Basin/Southwest...
As the mid-level jet associated with the digging mid-level trough
shifts eastward into the Upper Colorado River Valley, a corridor of
stronger, sustained surface winds (25-30 mph) will expand from
southeastern Nevada into the Colorado Plateau and overlap with very
low RH values of 10-15%. Exacerbated by dry, windy conditions on
D1/Friday, fuels will be very receptive, with ERCs already noted in
the 80-90+ percentiles. These conditions will promote an extended
period of critical fire weather conditions from southeastern Nevada
into the Upper Colorado River Basin and southern Wyoming. Localized
extremely critical wind/RH conditions are possible, particularly
across southeastern Utah and perhaps into southwestern Colorado
where latest high-res guidance suggests that the best overlap of
sustained southwesterly winds approaching 30 mph and very low RH
near 10% may occur. Pockets of fuels in this region are also noted
to be at or above the 95th percentile. A broader area of elevated
wind/RH conditions are expected across adjacent areas of the Great
Basin/Southwest where sustained winds of 15-25 mph are forecast to
overlap dry fuels and RH values of 10-20%.
The primary change with this outlook was to expand the Critical
highlights into north central Colorado based on the latest high-res
guidance. Consideration was given to the addition of a targeted
Extremely Critical area; however, some uncertainty remains regarding
the duration of overlap between sustained winds exceeding 30 mph and
RH values dropping below 10%. A portion of the Elevated highlights
were also trimmed across central Wyoming and the foothills of
northern Colorado owing to recent rainfall.
...Please see www.spc.noaa.gov/fire for graphic product...
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