WW 615 SEVERE TSTM AR MO MS TN 221915Z - 230300Z
URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 615
NWS Storm Prediction Center Norman OK
215 PM CDT Sat Aug 22 2026
The NWS Storm Prediction Center has issued a
* Severe Thunderstorm Watch for portions of
Northern into Central and Eastern Arkansas
Missouri Bootheel
Northern Mississippi
Western Tennessee
* Effective this Saturday afternoon and evening from 215 PM until
1000 PM CDT.
* Primary threats include...
Scattered damaging winds and isolated significant gusts to 75
mph possible
Isolated large hail events to 1.5 inches in diameter possible
SUMMARY...Scattered thunderstorms are forecast to develop and
intensify this afternoon and pose a risk for severe gusts and
perhaps an isolated threat for large hail. As additional storms
develop and clusters of storms evolve, the risk for severe gusts
will probably increase during the late afternoon through the early
evening as a linear cluster moves southeast. Severe gusts 60 to 75
mph are possible with this activity.
The severe thunderstorm watch area is approximately along and 90
statute miles north and south of a line from 10 miles north of
Russellville AR to 30 miles north northeast of Tupelo MS. 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 614...
AVIATION...A few severe thunderstorms with hail surface and aloft to
1.5 inches. Extreme turbulence and surface wind gusts to 65 knots. A
few cumulonimbi with maximum tops to 500. Mean storm motion vector
32025.
...Smith
WW 614 SEVERE TSTM NY OH PA WV LE LO 221720Z - 230100Z
URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 614
NWS Storm Prediction Center Norman OK
120 PM EDT Sat Aug 22 2026
The NWS Storm Prediction Center has issued a
* Severe Thunderstorm Watch for portions of
Western New York
Northern and Eastern Ohio
Western and Central Pennsylvania
Northern West Virginia
Lake Erie
Lake Ontario
* Effective this Saturday afternoon and evening from 120 PM until
900 PM EDT.
* Primary threats include...
Scattered damaging wind gusts to 70 mph likely
Isolated large hail events to 1.5 inches in diameter possible
SUMMARY...Scattered to numerous thunderstorms are forecast this
afternoon to move across the Watch area through the early evening.
The stronger thunderstorms will be capable of severe gusts capable
of wind damage (60 to 70 mph) and a risk for isolated large hail (1
to 1.5 inches in diameter). A gradual trend of initial cells and
line segments transitioning into bands of storms is expected with
time, with wind damage becoming the primary hazard.
The severe thunderstorm watch area is approximately along and 95
statute miles east and west of a line from 65 miles west northwest
of Buffalo NY to 35 miles south of Parkersburg WV. 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
1.5 inches. Extreme turbulence and surface wind gusts to 60 knots. A
few cumulonimbi with maximum tops to 450. Mean storm motion vector
23020.
...Smith
WW 0615 Status Updates
STATUS FOR WATCH 0615 HAS NOT BEEN ISSUED YET
WW 0614 Status Updates
STATUS REPORT ON WW 614
THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA.
..MEAD..08/22/26
ATTN...WFO...BUF...CLE...RLX...PBZ...ILN...CTP...
STATUS REPORT FOR WS 614
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
NYC003-009-013-029-037-063-073-121-221940-
NY
. NEW YORK COUNTIES INCLUDED ARE
ALLEGANY CATTARAUGUS CHAUTAUQUA
ERIE GENESEE NIAGARA
ORLEANS WYOMING
OHC005-007-009-013-019-029-031-033-035-043-045-053-055-059-067-
073-075-077-079-081-083-085-087-089-093-099-103-105-111-115-117-
119-121-123-127-133-139-143-147-151-153-155-157-163-167-169-
221940-
OH
. OHIO COUNTIES INCLUDED ARE
ASHLAND ASHTABULA ATHENS
BELMONT CARROLL COLUMBIANA
COSHOCTON CRAWFORD CUYAHOGA
ERIE FAIRFIELD GALLIA
GEAUGA GUERNSEY HARRISON
HOCKING HOLMES HURON
JACKSON JEFFERSON KNOX
LAKE LAWRENCE LICKING
MD 2087 CONCERNING SEVERE THUNDERSTORM WATCH 614... FOR CENTRAL AND EASTERN OHIO INTO NORTHERN WEST VIRGINIA AND WESTERN PARTS OF NEW YORK AND PENNSYLVANIA
Mesoscale Discussion 2087
NWS Storm Prediction Center Norman OK
0250 PM CDT Sat Aug 22 2026
Areas affected...central and eastern Ohio into northern West
Virginia and western parts of New York and Pennsylvania
Concerning...Severe Thunderstorm Watch 614...
Valid 221950Z - 222145Z
The severe weather threat for Severe Thunderstorm Watch 614
continues.
SUMMARY...The threat for mainly damaging wind gusts is expected to
continue across the watch area late this afternoon into evening.
DISCUSSION...Multiple bands of strong to severe thunderstorms are
ongoing within low-level confluence zones preceding the synoptic
cold front. As of 1945Z, the most intense convection was located
over far eastern OH, where several instances of wind damage have
been reported. Latest mesoanalysis indicates a plume of steep
low-level lapse rates in excess of 8 C/km has developed ahead of
that convective band, which should allow the damaging wind threat to
spread into western PA over the next hour.
Regional VWPs indicate generally weak low-level winds with pockets
of around 30 kt of deep-layer shear, which may be supportive of more
organized bowing/line segments capable of a comparatively greater
damaging wind threat. Otherwise, expect storms to remain somewhat
disorganized and shorter lived, but still capable of locally
damaging wind gusts.
..Mead.. 08/22/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...BUF...CTP...PBZ...RLX...CLE...ILN...
LAT...LON 39718266 40618267 41028300 41368307 41738204 42088121
42347989 42767905 43157852 43047819 41977864 40357942
39447982 39078044 38908120 38848189 38858239 39718266
MOST PROBABLE PEAK WIND GUST...55-70 MPH
MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN
MD 2086 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR EASTERN TEXAS INTO FAR WESTERN LOUISIANA
Mesoscale Discussion 2086
NWS Storm Prediction Center Norman OK
0246 PM CDT Sat Aug 22 2026
Areas affected...Eastern Texas into far western Louisiana
Concerning...Severe potential...Watch unlikely
Valid 221946Z - 222145Z
Probability of Watch Issuance...5 percent
SUMMARY...Isolated thunderstorms will be capable of strong to severe
downburst winds through early evening across eastern Texas and far
western Louisiana. This threat should be sufficiently isolated to
preclude watch issuance.
DISCUSSION...A recent 18 UTC sounding from SHV sampled very limited
inhibition remaining across far west/northwest LA. Further west into
eastern TX, temperatures are much warmer (100-106 F) with dewpoints
in the mid to upper 60s. Modifying the SHV sounding suggests that
SBCAPE values are likely approaching 3500 J/kg - much higher than
depicted by recent mesoanalysis estimates - with virtually no
lingering inhibition. Recent GOES imagery also shows an expanding
and deepening cumulus field across eastern TX, bounded to the north
by a residual outflow boundary and to the west by warmer 925-850 mb
temperatures/capping. Consequently, a corridor appears to be
emerging across east TX into western LA where thunderstorm
development is likely in the coming hours.
Weak forcing for ascent (mainly driven by weak low-level confluence
and/or strong surface heating) suggests that overall storm coverage
should remain somewhat limited. However, a combination of weak
deep-layer shear, steep low-level lapse rates on the order of 8-9
C/km, strong buoyancy, and 1.8 to 2.0 inch PWAT values should
support robust, water-loaded updraft development followed by strong
downbursts. Recent high-res ensemble guidance hints at this
potential and suggests localized swaths of 45-60 mph winds are
possible. This activity should peak by 4-6 PM CDT before gradually
diminishing with the loss of daytime heating after around 8 PM.
Trends will be monitored, but the expectation for more limited storm
coverage should negate the need for a watch.
..Moore/Smith.. 08/22/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...LCH...SHV...HGX...FWD...
LAT...LON 32669584 33119464 33139436 33009413 31379332 31159333
31009346 30339478 30329506 30429526 32229611 32509607
32669584
MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH
MD 2085 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR SOUTHERN TEXAS PANHANDLE INTO FAR SOUTHWEST OKLAHOMA
Mesoscale Discussion 2085
NWS Storm Prediction Center Norman OK
0218 PM CDT Sat Aug 22 2026
Areas affected...Southern Texas Panhandle into far southwest
Oklahoma
Concerning...Severe potential...Watch possible
Valid 221918Z - 222115Z
Probability of Watch Issuance...40 percent
SUMMARY...Thunderstorm development is anticipated across far
southwest Oklahoma and into the Texas Panhandle/northwest Texas by
late afternoon. This activity will pose a threat for severe
downburst winds as it spreads southwest through early evening. Watch
issuance is possible.
DISCUSSION...Recent surface observations are reporting temperatures
reaching into the 106-110 F range within the apex of a thermal ridge
across northwest TX. These temperatures are running 4-5 F warmer
than expected based on the latest high-res guidance, which implies
that boundary-layer mixing is likely deeper than depicted by
forecast soundings. Similarly, residual mixed-layer inhibition is
likely weaker than recent RAP mesoanalyses would suggest. The early
stages of boundary-layer cumulus development are becoming evident in
GOES imagery, suggesting that thunderstorm development appears
probable in the coming hours either along a residual outflow
boundary draped across southwest OK, along a diffuse/weak frontal
zone extending into the TX Panhandle, or in proximity to a weak
thermal low analyzed near the intersection of these two boundaries.
Although recent guidance does not appear to be capturing low-level
thermodynamic conditions well, HRRR/RRFS time-lagged guidance shows
a trends towards widely scattered to scattered thunderstorm
development by the 20-22 UTC period. Deep-layer shear will remain
weak and promote mainly disorganized convection, but the potential
for severe downbursts should increase as thunderstorms spread
south/southwest into the thermal ridge where low-level profiles will
be most optimal for near-surface downdraft accelerations. Explicit
wind gusts estimates from high-res solutions depict small swaths of
60-75 mph winds, which appear reasonable given the expectation of
poorly organized convection within a very hot/deeply mixed
environment. Convective trends will continue to be monitored, and
watch issuance is possible if convective coverage appears sufficient
for a more widespread severe wind threat.
..Moore/Smith.. 08/22/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...OUN...LUB...AMA...ABQ...
LAT...LON 33469894 33419928 33610233 33640275 33720299 33900312
34150316 34500308 34810289 35060253 35130166 35160062
35269914 35149890 34869876 33819857 33609867 33469894
MOST PROBABLE PEAK WIND GUST...65-80 MPH
MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN
MD 2084 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PORTIONS OF CENTRAL AND EASTERN WYOMING INTO THE WESTERN NEBRASKA PANHANDLE AND NORTHEAST COLORADO
Mesoscale Discussion 2084
NWS Storm Prediction Center Norman OK
0215 PM CDT Sat Aug 22 2026
Areas affected...portions of central and eastern Wyoming into the
western Nebraska Panhandle and northeast Colorado
Concerning...Severe potential...Watch unlikely
Valid 221915Z - 222145Z
Probability of Watch Issuance...20 percent
SUMMARY...The threat for isolated occurrences of large hail and
severe wind gusts is expected to increase by mid-afternoon and
continue through this evening. A watch is currently not anticipated
due to the limited coverage of the threat.
DISCUSSION...Recent trends in visible satellite imagery show
deepening moist convection along the Laramie Mountains and CO Front
Range with additional development likely ahead of a well-defined MCV
moving through central WY. Beneath a plume of steep mid-level lapse
rates, current surface observations indicate a moist boundary layer
characterized by dewpoints in the mid 50s to low 60s, yielding
MLCAPE of 1000-1500 J/kg. Latest objective analysis suggests the air
mass across the adjacent High Plains remains capped; however,
continued daytime heating and the glancing influence of the WY MCV
should allow initial terrain-anchored storms to move into lower
elevations later this afternoon into evening.
Current VWPs and RAP-based forecast soundings indicate vertically
veering wind profiles with around 30 kt of deep-layer shear, which
will be supportive of at least episodic supercell structures capable
of large hail. The potential for isolated severe wind gusts may
become more likely by early evening, especially if storms can merge
into clusters.
..Mead/Smith.. 08/22/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...UNR...BOU...CYS...RIW...
LAT...LON 39800550 41380567 42410617 42980659 43970678 44480622
44330536 43750482 42360365 40850314 40080324 39670350
39320422 39330484 39800550
MOST PROBABLE PEAK WIND GUST...55-70 MPH
MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN
MD 2083 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR WEST VIRGINIA AND MARYLAND PANHANDLES INTO NORTHERN AND CENTRAL VIRGINIA
Mesoscale Discussion 2083
NWS Storm Prediction Center Norman OK
0127 PM CDT Sat Aug 22 2026
Areas affected...West Virginia and Maryland Panhandles into northern
and central Virginia
Concerning...Severe potential...Watch unlikely
Valid 221827Z - 222030Z
Probability of Watch Issuance...20 percent
SUMMARY...Isolated severe storms appear possible from mid-afternoon
into this evening. Damaging wind gusts are the primary hazard. A
watch issuance is not anticipated due to the limited areal coverage
of the threat.
DISCUSSION...Recent thunderstorm development has occurred over the
WV Panhandle, northwest of Harrisonburg, VA, amidst a moist and
moderately unstable air mass with MLCAPE of 1500-2000 J/kg. Farther
east along the lee side of the Blue Ridge, visible satellite imagery
indicates deepening cumulus within a low-level upslope regime.
Latest time-lagged HRRR and RRFS ensemble guidance suggests that a
small cluster of thunderstorms may evolve out of those areas of
deepening moist convection over northern VA later this afternoon
into evening.
The current VWP from Charleston, WV is sampling 30-40 kt of westerly
winds above 4 km AGL, which may contribute to some organization as
updrafts continue to mature this afternoon. When coupled with
steepening low-level lapse rates, the environment appears supportive
of locally damaging wind gusts as storms progress east across the
discussion area.
..Mead/Smith.. 08/22/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...AKQ...LWX...RNK...
LAT...LON 38487947 38807935 39137920 39617890 39707838 39617788
39107736 38497732 38027754 37647808 37677895 37687919
37937950 38247953 38487947
MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH
MD 2082 CONCERNING SEVERE POTENTIAL...WATCH LIKELY FOR PORTIONS OF THE MID SOUTH
Mesoscale Discussion 2082
NWS Storm Prediction Center Norman OK
0109 PM CDT Sat Aug 22 2026
Areas affected...portions of the Mid South
Concerning...Severe potential...Watch likely
Valid 221809Z - 222015Z
Probability of Watch Issuance...80 percent
SUMMARY...Scattered damaging/severe wind gusts and isolated large
hail are expected across portions of the Mid South this afternoon. A
Severe Thunderstorm Watch will likely be needed.
DISCUSSION...Latest surface analysis depicts a west-east oriented
cold front extending from far southern Illinois into southern
Missouri and Kansas. Also evident in visible satellite imagery are
an MCV located in close proximity to ongoing convection across far
southeastern Kansas and a surface confluence zone across northern
Arkansas demarcated by a zone of developing cumulus. As this MCV and
surface cold front continue to progress south-southeastward through
mid-afternoon, guidance suggests that ongoing convection should
intensify and/or additional development will occur along the
aforementioned boundaries amid a moderately unstable environment.
As convective coverage increases through the mid-afternoon, enhanced
mid-level flow associated with the MCV (40-50 kts sampled by the
Tulsa/Wichita VWPs along the southern flank of the MCV) will aid in
the organization of convection into one or more linear clusters.
Scattered damaging/severe wind gusts (and potentially a few
significant gusts to 75-80 mph) are likely to accompany this cluster
given the enhanced mid-level flow and presence of very steep
low-to-mid level lapse rates below 600 mb (as depicted by recent
objective analysis and sampled by the 12 UTC LZK observed sounding).
A Severe Thunderstorm Watch will likely be needed in the next 1-2
hours to address this severe risk.
..Chalmers/Smith.. 08/22/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...MEG...JAN...LZK...SGF...TSA...
LAT...LON 35779399 35159363 34349252 33509112 33518998 33788906
34528871 34998886 35608919 36039020 36829284 36679353
36239395 35779399
MOST PROBABLE PEAK WIND GUST...65-80 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
1130 AM CDT Sat Aug 22 2026
Valid 221630Z - 231200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE OHIO VALLEY INTO THE CENTRAL APPALACHIANS AND THE MID SOUTH...
...SUMMARY...
Scattered severe thunderstorms are possible over parts of the Mid
South with 60 to 75 mph gusts being the primary hazard. Scattered
damaging winds are possible this afternoon across parts of the Ohio
Valley into the central Appalachians.
...Ohio Valley into the Central Appalachians and Tennessee/Lower
Mississippi Valleys...
An upper trough continues to dig southeast across the southwest
Great Lakes during the midday as a surface front advances slowly
east across the southern Great Lakes and OH Valley. Late morning
surface analysis places a moist plume (65 to 70 deg F surface
dewpoints) extending northeastward ahead of the front from the lower
OH Valley into northeast OH. Visible satellite imagery shows a
swelling cumulus field across the upper OH Valley where moderate
buoyancy has developed. A gradual increase in thunderstorm coverage
and intensity is expected, with 20-30 kt of effective bulk shear
fostering enough updraft organization for multicell clusters capable
of producing scattered damaging winds. See MCD #2081 for short-term
details. These thunderstorms will spread eastward from the upper OH
Valley into the central Appalachians this afternoon and evening
before eventually weakening with eastward extent. Isolated hail may
occur with the stronger cores that develop, but the poor mid-level
lapse rates present may limit this threat to some extent. There
also appears to be some chance for strong to locally severe
thunderstorms to develop along/east of the Blue Ridge Mountains this
afternoon. If this occurs, then occasional damaging winds would be
the main threat with this activity.
...Southern/Central Plains into the Mid South...
Satellite imagery late this morning shows a pair of convectively
enhanced mid-level vorticity maxima moving southeast over eastern
KS/OK on the eastern periphery of upper ridging centered over NM.
Weak thunderstorm activity continues to progress southeast over
eastern KS towards the Ozarks, where the airmass has heated near 90
deg F to the downstream of greater cloud cover. Surface analysis
this morning showed a reservoir of richer moisture (lower 70s deg F
surface dewpoints) south of a stalled west-east frontal zone.
Additional heating/destabilization ahead of the southeastward-moving
thunderstorms and associated MCV will act to pre-condition the
environment to support a greater risk for severe gusts and wind
damage across parts of the Mid South this afternoon and early
evening. CAM model guidance both from a model core and time-lagged
ensemble, suggest the eventual development of a linear cluster
developing over the Ozarks and moving east-southeast into a
hot/unstable airmass featuring very steep 0-3 km lapse rates. Mid
to upper-level flow will tend to weaken with southeast extent, but
ample cloud-bearing shear for storm organization is evident. Have
upgraded a corridor from northern ARK into northern MS where
confidence is highest on an MCS developing and an associated risk
for severe gusts and wind damage.
Additional isolated storm development is expected later today across
parts of the southern Great Plains. Moderate to locally strong
instability, very steep low-level lapse rates, and moderate
northwesterly deep-layer shear should support some
clustering/updraft organization. Occasional hail and severe gusts
may occur as thunderstorms spread southward this afternoon/evening.
...Central High Plains/Front Range...
A separate area of convection is forecast to develop this afternoon
along the Front Range/Laramie Mountains in a weak post-frontal
low-level upslope regime. While effective bulk shear should be
somewhat weaker across this region, a narrow corridor of greater
instability is forecast across the central High Plains. This may
support loosely organized multicells and marginal supercells with an
isolated severe hail/wind threat.
...Great Basin/Northern Rockies into the Northwest...
Upper ridging will remain prominent from the Southwest into the
northern Rockies/High Plains today. On the western periphery of
this ridging, an upper trough/low will move northward along/near the
coast of the Pacific Northwest. Enhanced south-southwesterly
mid-level flow will overspread parts of the Great Basin, northern
Rockies, and Northwest through the period, with the strongest winds
forecast over WA/OR. Low-level moisture remains fairly limited over
most of these regions, with somewhat greater surface dewpoints
present over parts of the Great Basin.
Diurnal heating should support modest destabilization and weak
instability from the northern Great Basin into the interior Pacific
Northwest and northern Rockies. Thunderstorms will develop this
afternoon as the large-scale ascent preceding the upper trough/low
overspreads these regions in tandem with orographic effects across
the higher terrain. Where low-level lapse rates can become
sufficiently steepened with a dry/well-mixed sub-cloud layer,
isolated severe/damaging winds may occur. The overall severe threat
should be limited by weak instability.
..Smith/Chalmers.. 08/22/2026
SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0256 PM CDT Sat Aug 22 2026
Valid 222000Z - 231200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF
THE OHIO VALLEY INTO THE CENTRAL APPALACHIANS...THE MID SOUTH...AND
THE SOUTHERN GREAT PLAINS...
...SUMMARY...
Scattered severe thunderstorms are possible over parts of the Mid
South and southern Great Plains with 60 to 75 mph gusts being the
primary hazard. Scattered damaging winds also remain possible this
afternoon across parts of the Ohio Valley into the central
Appalachians.
...20z Update...
...Southern Great Plains...
The primary change with this outlook update was an upgrade to a
Level 2/Slight risk for portions of northwest Texas and the Texas
Panhandle driven by the inclusion of 15% wind probabilities based on
the latest CAM and time-lagged ensemble guidance. The 5% wind
probability and CIG1 were similarly expanded across adjacent
portions of the southern Great Plains. See Mesoscale Discussion 2085
for additional short-term details.
...Mid Atlantic...
Isolated convective initiation is ongoing across portions of the
central Blue Ridge in far northwestern Virginia as of 1955 UTC.
Latest CAM/time-lagged ensemble guidance continues to suggest the
potential for some upscale growth/clustering of convection
downstream across northern Virginia. Some consideration was given to
a targeted upgrade to a Level 2/Slight risk (via the inclusion of a
15% wind probability) for this area; however, weak low-level flow
sampled by the Sterling (LWX) VWP and cooler downstream temperatures
in the upper-70s F lend uncertainty to the coverage of the resultant
severe risk and precluded an upgrade at this time. A locally greater
risk for damaging wind gusts could materialize should a cluster of
storms develop, however. See MCD 2083 for additional details.
Elsewhere, only minor adjustments were made based on recent
convective/observational trends and the latest forecast guidance.
See the text below and Mesoscale Discussions 2084 and 2086 for
additional details.
..Chalmers/Moore.. 08/22/2026
.PREV DISCUSSION... /ISSUED 1130 AM CDT Sat Aug 22 2026/
...Ohio Valley into the Central Appalachians and Tennessee/Lower
Mississippi Valleys...
An upper trough continues to dig southeast across the southwest
Great Lakes during the midday as a surface front advances slowly
east across the southern Great Lakes and OH Valley. Late morning
surface analysis places a moist plume (65 to 70 deg F surface
dewpoints) extending northeastward ahead of the front from the lower
OH Valley into northeast OH. Visible satellite imagery shows a
swelling cumulus field across the upper OH Valley where moderate
buoyancy has developed. A gradual increase in thunderstorm coverage
and intensity is expected, with 20-30 kt of effective bulk shear
fostering enough updraft organization for multicell clusters capable
of producing scattered damaging winds. See MCD #2081 for short-term
details. These thunderstorms will spread eastward from the upper OH
Valley into the central Appalachians this afternoon and evening
before eventually weakening with eastward extent. Isolated hail may
occur with the stronger cores that develop, but the poor mid-level
lapse rates present may limit this threat to some extent. There
also appears to be some chance for strong to locally severe
thunderstorms to develop along/east of the Blue Ridge Mountains this
afternoon. If this occurs, then occasional damaging winds would be
the main threat with this activity.
...Southern/Central Plains into the Mid South...
Satellite imagery late this morning shows a pair of convectively
enhanced mid-level vorticity maxima moving southeast over eastern
KS/OK on the eastern periphery of upper ridging centered over NM.
Weak thunderstorm activity continues to progress southeast over
eastern KS towards the Ozarks, where the airmass has heated near 90
deg F to the downstream of greater cloud cover. Surface analysis
this morning showed a reservoir of richer moisture (lower 70s deg F
surface dewpoints) south of a stalled west-east frontal zone.
Additional heating/destabilization ahead of the southeastward-moving
thunderstorms and associated MCV will act to pre-condition the
environment to support a greater risk for severe gusts and wind
damage across parts of the Mid South this afternoon and early
evening. CAM model guidance both from a model core and time-lagged
ensemble, suggest the eventual development of a linear cluster
developing over the Ozarks and moving east-southeast into a
hot/unstable airmass featuring very steep 0-3 km lapse rates. Mid
to upper-level flow will tend to weaken with southeast extent, but
ample cloud-bearing shear for storm organization is evident. Have
upgraded a corridor from northern ARK into northern MS where
confidence is highest on an MCS developing and an associated risk
for severe gusts and wind damage.
Additional isolated storm development is expected later today across
parts of the southern Great Plains. Moderate to locally strong
instability, very steep low-level lapse rates, and moderate
northwesterly deep-layer shear should support some
clustering/updraft organization. Occasional hail and severe gusts
may occur as thunderstorms spread southward this afternoon/evening.
...Central High Plains/Front Range...
A separate area of convection is forecast to develop this afternoon
along the Front Range/Laramie Mountains in a weak post-frontal
low-level upslope regime. While effective bulk shear should be
somewhat weaker across this region, a narrow corridor of greater
instability is forecast across the central High Plains. This may
support loosely organized multicells and marginal supercells with an
isolated severe hail/wind threat.
...Great Basin/Northern Rockies into the Northwest...
Upper ridging will remain prominent from the Southwest into the
northern Rockies/High Plains today. On the western periphery of
this ridging, an upper trough/low will move northward along/near the
coast of the Pacific Northwest. Enhanced south-southwesterly
mid-level flow will overspread parts of the Great Basin, northern
Rockies, and Northwest through the period, with the strongest winds
forecast over WA/OR. Low-level moisture remains fairly limited over
most of these regions, with somewhat greater surface dewpoints
present over parts of the Great Basin.
Diurnal heating should support modest destabilization and weak
instability from the northern Great Basin into the interior Pacific
Northwest and northern Rockies. Thunderstorms will develop this
afternoon as the large-scale ascent preceding the upper trough/low
overspreads these regions in tandem with orographic effects across
the higher terrain. Where low-level lapse rates can become
sufficiently steepened with a dry/well-mixed sub-cloud layer,
isolated severe/damaging winds may occur. The overall severe threat
should be limited by weak instability.
SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1230 PM CDT Sat Aug 22 2026
Valid 231200Z - 241200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF
CENTRAL AND EASTERN MONTANA AND PARTS OF THE EASTERN GREAT BASIN
INTO THE CENTRAL ROCKIES...
...SUMMARY...
Strong thunderstorm activity posing at least some risk for severe
hail and wind appears possible across parts of the northern Rockies
and Great Plains, and across parts of the eastern Great Lakes to the
Northeast, Sunday through Sunday night.
...Synopsis...
Upper ridging will prevail across the western CONUS as an upper
trough slowly traverses the Northeast tomorrow (Sunday). A mid-level
impulse will crest the upper ridge tomorrow afternoon across the
northern Rockies while a small impulse embedded in the
aforementioned upper trough overspreads the northern Appalachians.
From the northern Rockies to northern High Plains, as well as parts
of the Northeast, stronger flow above the boundary layer will
promote adequate vertical wind shear, in tandem with buoyancy, to
promote strong to severe thunderstorms. Elsewhere from the central
Rockies to the Gulf/Carolina coastlines, strong surface heating amid
pockets of low-level moisture will support scattered thunderstorm
development, with an isolated severe storm possible.
...Northern Rockies...
By mid to late afternoon, a well-mixed boundary layer should develop
beneath a plume of cooler temperatures aloft (e.g. 8+ C/km mid-level
lapse rates) with the passage of the aforementioned mid-level
impulse. A belt of stronger mid- to -upper level westerly flow will
also accompany this impulse, resulting in elongated hodographs and
30-40 kts of effective bulk (speed) shear coinciding with the steep
low- and mid-level lapse rates. Multicells and transient supercells
should develop, accompanied by a risk of severe gusts and perhaps an
instance or two of hail. A gust over 75 mph is possible.
...Northern High Plains into South Dakota...
Convective evolution and morphology remains unclear in this region.
Steep lapse rates will emanate from the northern Rockies and
overspread a moistening warm sector (e.g. mid 60s F dewpoints),
yielding 2000+ J/kg MLCAPE. Modestly curved and elongated hodographs
suggest multicells and supercells as the main storm mode, at least
initially. Severe gusts/hail would accompany these storms if they
can become sustained. There is also some indication by the latest
CAMS that storms may merge into a cold-pool-driven MCS, though
guidance consensus is weak on this scenario. Nonetheless, any MCS
development that does occur would support severe gusts, including a
75+ mph gust.
...Portions of the eastern Great Basin to the central Rockies...
A cluster of multicell storms should develop around the eastern
Great Basin into the central Rockies by afternoon peak heating.
Stronger flow aloft will glance the region to the north, atop a
strongly mixed boundary layer. Forecast soundings show classic
inverted-V profiles extending to 500 mb, with surface-500 mb lapse
rates reaching at least 9 C/km. As such, severe gusts are possible
with the stronger multicells that form.
...Portions of the Northern Appalachians into New England...
By afternoon, surface temperatures should warm well into the 70s F
as earlier showers and thunderstorms make way for at least partly
clearing skies. While not overly steep, mid-level lapse rates
exceeding 6.5 C/km will result in marginal buoyancy, amid stronger
flow aloft (yielding elongated hodographs). A couple instances of
damaging gusts/hail will be possible with the stronger multicells
that manage to sustain themselves.
...Gulf to Carolina Coastlines...
A heated and moist boundary layer should develop by afternoon given
the presence of mid 70s F surface dewpoints and temperatures rising
well into the 80s F. Such rich low-level moisture will support
2000-4000 J/kg MLCAPE from LA to extreme eastern NC despite
mid-level lapse rates only reaching 6-6.5 C/km. Across the Gulf
Coast, pulse-cellular storms are expected given weak flow aloft,
with damaging gusts originated from wet downbursts the main threat.
Along the Carolina Coastline, southwesterly mid-level flow will be a
bit stronger given the upper trough glancing by to the north.
Multicells capable of isolated severe gusts are possible. Locally
higher severe probabilities may be needed in future Day 1 outlooks
if greater storm coverage becomes apparent.
...Portions of southern Arizona...
Locally stronger southeasterly mid-level flow will pivot around the
upper ridge and overspread a deep and dry boundary layer by late
afternoon/early evening. Meanwhile, surface temperatures around 100
F, amid 60 F surface dewpoints and overspread by modestly cooler
temperatures aloft, will yield 9+ C/km tropospheric lapse rates and
over 2000 J/kg MLCAPE. Given the modest flow aloft and
aforementioned buoyancy, a few organized multicells may occur,
accompanied by an isolated severe gust threat.
..Squitieri.. 08/22/2026
SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0227 PM CDT Sat Aug 22 2026
Valid 241200Z - 251200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE NORTHERN GREAT BASIN TO THE HIGH PLAINS AND NORTHERN
PLAINS...PARTS OF THE GULF COAST...AND MAINE...
...SUMMARY...
Thunderstorms with at least isolated severe gusts/hail are possible
across the northern Great Basin to the High Plains and northern
Plains Monday afternoon and evening. A couple of damaging gusts may
also occur with storms in Maine and along parts of the Gulf Coast.
...Synopsis...
An upper ridge will remain in place across the western and central
CONUS while an upper trough begins to eject into the Atlantic from
New England on Monday. The embedded impulse responsible for cresting
the ridge over the northern Rockies and encouraging severe storm
development on Day 2 (Sunday) will overspread the northern High
Plains on Monday. Weak lee troughing over the Plains will encourage
modest low-level moisture advection beneath stronger westerly flow
aloft, resulting in enough deep-layer ascent, amid coinciding
buoyancy and vertical wind shear, to support isolated strong to
severe thunderstorms.
...Central High Plains to the northern Plains...
Upslope flow of 60s F surface dewpoints beneath 8 C/km mid-level
lapse rates along the central and northern High Plains will yield
2000-3000 J/kg MLCAPE as a mid-level impulse begins to overspread
the region. Over 30 kts of 500 mb flow and resultant deep-layer
shear will coincide with this buoyancy, supporting the development
of multicells and perhaps supercells by late Monday afternoon.
Should more sustained supercells develop, an instance or two of 2+
inch diameter hail or a 75+ mph gust cannot be ruled out given the
aforementioned mid-level lapse rates. Slight risk probabilities may
be needed in future outlooks pending higher confidence in greater
storm coverage.
...Parts of the northern Great Basin to central Rockies...
A deep and dry boundary layer should develop by afternoon peak
heating, resulting in inverted-V thermodynamic profiles from the
northern Great Basin into the central Rockies. Stronger westerly
mid-level flow will overspread this dry and unstable boundary layer,
promoting elongated hodographs and the tendency for storms to
organize into multicells. Given the organized storm mode and
evaporative cooling potential with the dry boundary layer in place,
a few severe gusts may occur with the stronger storms.
...Maine...
Deep-layer ascent ahead of the ejecting upper trough will support
scattered thunderstorm development during the late morning into the
afternoon hours. A belt of 60 kt 500 mb southwesterly flow will
pivot around the upper trough and overspread Main during the
afternoon, when buoyancy will be maximized. MLCAPE may exceed 750
J/kg with over 50 kts of effective bulk/speed shear given highly
elongated hodographs. Therefore, any storms that develop may become
multicellular or transient supercellular in nature, posting an
isolated damaging gust/hail threat through the afternoon.
...Parts of the Gulf Coast...
Another hot and humid day is expected along the Gulf Coast, where
strong surface heating amid mid 70s F dewpoints will yield MLCAPE
over 2000 J/kg. Despite weak tropospheric flow, enough
moisture-fueled buoyancy will support the potential for wet
downbursts capable of damaging gusts during the afternoon.
..Squitieri.. 08/22/2026
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1132 AM CDT Sat Aug 22 2026
Valid 221700Z - 231200Z
...CRITICAL FIRE WEATHER AREA FOR MUCH OF NORTHERN
WASHINGTON...NORTHERN IDAHO PANHANDLE AND FAR NORTHWESTERN
MONTANA...
...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF
SOUTH-CENTRAL/SOUTHEAST WASHINGTON AND FAR NORTH-CENTRAL OREGON...
...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF NORTHEAST
CALIFORNIA...NORTHWEST NEVADA...AND SOUTH-CENTRAL/SOUTHEAST
OREGON...
...Dry Thunderstorms - Northern Intermountain West and northern
Rockies...
Current radar and satellite imagery depict scattered showers and
thunderstorms across eastern OR into central WA, as a robust
upper-level trough invades the Pacific Northwest. Precipitation
efficiency has been limited with very few surface observation sites
showing meaningful rainfall due to fast northward/northeastward
trajectories of the high-based showers/thunderstorms. Latest CAM
ensemble guidance and forecast soundings continue to depict a
lingering, dry sub-cloud layer across eastern WA, northeastern OR
and the ID Panhandle through the evening and overnight hours. The
arrival of a 50+ knot 500 mb jet and associated increasing shear and
forcing for ascent will likely aid in nocturnal convection atop this
residual dry boundary layer. Despite increasing Pacific moisture
leading to PWAT values in the 0.8-1.1" range across this region,
storm motions upwards of 40 mph will limit rainfall amounts over a
receptive fuelscape, increasing lightning ignition potential. Thus,
scattered dry thunderstorm highlights were extended eastward farther
into northwest MT and likewise southward into far southeastern WA
and ID Panhandle where greater convective coverage is expected.
...Dry/Windy Conditions - Northern/Central Intermountain West...
Only minor eastward expansion of existing critical and elevated
highlights were needed across portions of the northern Great Basin
into central ID based on latest model guidance consensus and current
surface observation trends.
..Williams.. 08/22/2026
.PREV DISCUSSION... /ISSUED 0200 AM CDT Sat Aug 22 2026/
...Synopsis...
Along the northwestern periphery of an expansive upper ridge
centered on the central/southern Rockies, a robust midlevel trough
and accompanying south-southwesterly jet streak will overspread the
Northwest through the period.
...Dry Thunderstorms - Northern Intermountain West and northern
Rockies...
The 00Z observed soundings across parts of the central Great Basin
show ample midlevel moisture, which will continue spreading
northward across the northern Intermountain West and northern
Rockies today. Diurnal heating/boundary-layer mixing beneath the
moist plume will yield a broad area of weak instability by this
afternoon -- characterized by inverted-V thermodynamic profiles. As
midlevel height falls/forcing for ascent preceding the midlevel
trough overspread this instability, isolated to scattered
fast-moving thunderstorms will track northward across the region
this afternoon and evening.
The greatest coverage of high-based storms is expected across parts
of northern WA into the northern ID Panhandle, where forcing for
ascent will be strongest. While a mix of wet/dry storms is possible,
the fast storm motions and dry boundary layer should limit rainfall
amounts. Given very receptive fuels, the risk of lightning-induced
ignitions will be maximized here. Additionally, enhanced deep-layer
wind shear related to the upper-level jet will promote some
strong-severe storm clusters, capable of producing severe wind gusts
and hail. See the SPC Day 1 Convective Outlook for more details on
the severe risk.
...Dry/Windy Conditions - Northern/Central Intermountain West...
The strong deep-layer south-southwesterly flow accompanying the
midlevel trough will result in strong downslope flow off the
Cascades and northern Sierra. This will result in a broad area of
15-20 percent afternoon RH and 15-25 mph sustained
west-southwesterly surface winds. The strongest winds are expected
within terrain-favored areas, such as the Columbia Basin and in the
lee of the southern Cascades -- where dry/receptive fuels will
support critical fire-weather conditions during the afternoon.
...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
0253 PM CDT Sat Aug 22 2026
Valid 231200Z - 241200Z
...Southern Plains...
A subtle embedded mid-level short wave will enter the Southern
Plains on D2/Sunday, aiding in isolated shower and thunderstorm
development by Sunday afternoon. A dry boundary layer with large
surface dew point depressions as temperatures climb into the lower
100s F will promote evaporation of high-based thunderstorm rain
cores over the northern TX Panhandle, OK Panhandle and far western
OK. Isolated dry thunderstorm highlights have been introduced into
the aforementioned area as fuels remain extremely dry and receptive.
Additionally, a slight westward expansion of existing elevated
highlights across the Southern High Plains was made based on latest
forecast guidance and dry fuel conditions.
...Northern Rockies into Central Montana...
Model guidance trends has depicted a faster progressing mid-level
trough through the Northwestern U.S. through Sunday. With this
accelerated trough advancement, forcing for ascent has been shifted
primarily into far northeastern WA and the ID Panhandle for Sunday
as the mid-level jet enters the Northern Rockies. A slight pullback
for isolated dry thunderstorm highlights was made across
north-central WA. A broader dry thunderstorm threat remains over
central MT Sunday, followed by dry and breezy conditions and
elevated fire weather concerns later in the day as drier westerly
flow filters into the region.
..Williams.. 08/22/2026
.PREV DISCUSSION... /ISSUED 0201 AM CDT Sat Aug 22 2026/
...Synopsis...
A midlevel trough will continue eastward across the Northwest and
northern Rockies during the day -- where ample midlevel moisture
will remain in place atop a diurnally deepening boundary layer.
Related forcing for ascent preceding the trough will promote
isolated to widely scattered fast-moving thunderstorms across parts
of the northern Rockies and Northwest during the afternoon and early
evening. Given 0.7-0.9 inch PW, a dry/well-mixed boundary layer, and
fast storm motions, a mix of wet/dry thunderstorms will pose a risk
of lightning-induced ignitions and gusty/erratic outflow winds atop
receptive fuels. Additionally, enhanced deep-layer
west-southwesterly flow accompanying the midlevel trough will
overspread the warm/dry air mass in place across the northern
Rockies, yielding dry/breezy (elevated) fire-weather conditions
during the afternoon.
Farther south, dry/breezy southerly return flow will develop across
parts of the southern High Plains -- in response to a passing
low-amplitude midlevel trough. These dry/breezy conditions atop
increasingly receptive fuels will favor elevated fire-weather
conditions during the afternoon.
...Please see www.spc.noaa.gov/fire for graphic product...
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