RSS Mesoscale Discussions from Storm Prediction Center
WW 469 SEVERE TSTM NE SD WY 072225Z - 080500Z
URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 469
NWS Storm Prediction Center Norman OK
425 PM MDT Tue Jul 7 2026
The NWS Storm Prediction Center has issued a
* Severe Thunderstorm Watch for portions of
Northwest Nebraska
Western and Central South Dakota
Northeast Wyoming
* Effective this Tuesday afternoon and evening from 425 PM until
1100 PM MDT.
* Primary threats include...
Scattered damaging winds and isolated significant gusts to 75
mph possible
Scattered large hail and isolated very large hail events to 2.5
inches in diameter possible
A tornado or two possible
SUMMARY...A mix of supercells and clusters should pose a threat for
both large hail and severe/damaging winds this afternoon and evening
as they develop slowly eastward. Isolated very large hail up to
2-2.5 inches in diameter may occur with any sustained supercells,
and occasional significant gusts up to 75 mph appear possible if a
cluster can form later this evening.
The severe thunderstorm watch area is approximately along and 60
statute miles north and south of a line from 20 miles southwest of
Gillette WY to 55 miles southeast of Pierre SD. For a complete
depiction of the watch see the associated watch outline update
(WOUS64 KWNS WOU9).
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
2.5 inches. Extreme turbulence and surface wind gusts to 65 knots. A
few cumulonimbi with maximum tops to 550. Mean storm motion vector
26025.
...Gleason
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WW 0469 Status Updates
STATUS REPORT ON WW 469
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 5 NE ANW TO
10 SE CDR.
FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 1537
..MOORE..07/08/26
ATTN...WFO...LBF...UNR...ABR...
STATUS REPORT FOR WS 469
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
SDC007-013-017-019-021-031-033-041-045-047-049-055-059-065-069-
071-075-081-085-089-093-095-102-103-107-115-117-119-121-123-129-
080240-
SD
. SOUTH DAKOTA COUNTIES INCLUDED ARE
BENNETT BROWN BUFFALO
BUTTE CAMPBELL CORSON
CUSTER DEWEY EDMUNDS
FALL RIVER FAULK HAAKON
HAND HUGHES HYDE
JACKSON JONES LAWRENCE
LYMAN MCPHERSON MEADE
MELLETTE OGLALA LAKOTA PENNINGTON
POTTER SPINK STANLEY
SULLY TODD TRIPP
WALWORTH
WYC005-011-045-080240-
WY
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MD 1538 CONCERNING SEVERE THUNDERSTORM WATCH 469... FOR NORTHEAST SOUTH DAKOTA INTO CENTRAL MINNESOTA
Mesoscale Discussion 1538
NWS Storm Prediction Center Norman OK
0854 PM CDT Tue Jul 07 2026
Areas affected...Northeast South Dakota into central Minnesota
Concerning...Severe Thunderstorm Watch 469...
Valid 080154Z - 080400Z
The severe weather threat for Severe Thunderstorm Watch 469
continues.
SUMMARY...A cluster of severe thunderstorms will likely spread east
into central Minnesota over the next few hours. The downstream
environment should support a continued severe wind threat.
Downstream watch issuance probably be needed to address this
concern.
DISCUSSION...An elevated thunderstorm cluster migrating southeast
across the Aberdeen, SD region has begun producing severe winds at
the surface between 60-70 mph. This, coupled with a recent uptick in
lightning counts and cooling cloud-top temperatures, strongly
suggests that the cluster is utilizing the higher buoyancy in place
across the region. Based on current storm tracks and latest
mesoanalyses, this storm will continue to push into a regional
buoyancy maximum, so further intensification appears probable over
the next hour or so. Additionally, surface observations show a warm
frontal zone draped from far northeast SD into central MN that is
well aligned with the deep-layer bulk shear vector. This may act as
a foci for storm propagation through the next few hours where a
greater chance for severe wind could emerge.
New storm development south of the ongoing cluster also appears
possible over the next 1-2 hours as an outflow boundary from the
cluster collides with a meandering boundary to the south. Any storms
developing within this zone will likely also pose a threat for
severe hail and eventually severe wind if/when upscale clustering
occurs. Regardless, downstream watch issuance into central MN
appears probable in the coming hours as storms continue to spread
east.
..Moore.. 07/08/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...MPX...FGF...FSD...ABR...
LAT...LON 44049544 44259651 44549674 44919683 45209681 45549660
45709646 45869611 45729433 45509398 45139385 44829389
44489409 44249436 44079486 44049544
MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 90 MPH
MOST PROBABLE PEAK WIND GUST...65-80 MPH
MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN
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MD 1537 CONCERNING SEVERE THUNDERSTORM WATCH 469... FOR FAR NORTHEAST WYOMING INTO SOUTH DAKOTA
Mesoscale Discussion 1537
NWS Storm Prediction Center Norman OK
0808 PM CDT Tue Jul 07 2026
Areas affected...Far northeast Wyoming into South Dakota
Concerning...Severe Thunderstorm Watch 469...
Valid 080108Z - 080315Z
The severe weather threat for Severe Thunderstorm Watch 469
continues.
SUMMARY...The potential for severe hail and wind continues across
far northeast WY into southwest to northeast South Dakota. A gradual
uptick in thunderstorm coverage is possible in the next few hours
across central to northeast South Dakota.
DISCUSSION...Although intense convection has been rather sparse
across much of WW 469 over the past couple of hours, a handful of
severe hail and wind reports have been noted across northeast WY,
and MRMS MESH estimates show a few cores capable of producing severe
hail across north-central SD.
While convection has been fairly isolated thus far, guidance
continues to suggest an uptick in thunderstorm activity is probable
in the coming hours. This will be driven by a strengthening
nocturnal jet that will augment isentropic ascent atop a boundary
draped across the state, and will likely lift most-unstable parcels
through residual inhibition to their LFCs (as suggested by the 00z
ABR RAOB). Convection along and north of the boundary will likely
pose a large hail threat given the strong deep-layer wind shear, but
some clustering and propagation along the boundary is possible and
may pose a more robust threat for severe wind.
Further west, high-based convection across northeast WY will likely
continue to propagate eastward. Further intensification of this
activity appears possible as it spreads east and south of the Black
Hills and into a slightly cooler, but more buoyant air mass where
effective bulk shear values are near 40 knots (per the 00z UNR
RAOB).
..Moore.. 07/08/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...FGF...FSD...ABR...BIS...UNR...CYS...
LAT...LON 43050363 43420417 43730444 44030468 44370468 44590430
44640342 44870156 45230087 45480046 45670000 45869918
45919858 45959776 45849736 45629722 45369709 45069727
44779777 44439852 43829957 43470042 43170161 43080236
43020300 43050363
MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 90 MPH
MOST PROBABLE PEAK WIND GUST...55-70 MPH
MOST PROBABLE PEAK HAIL SIZE...1.50-2.50 IN
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SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0757 PM CDT Tue Jul 07 2026
Valid 080100Z - 081200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE NORTHERN PLAINS AND UPPER MISSISSIPPI VALLEY...
...SUMMARY...
Thunderstorms with severe wind gusts potentially above 75 mph, and
isolated large hail are expected across parts of the northern Plains
and upper Mississippi Valley from this evening into the early
overnight period.
...Northern Plains/Upper Mississippi Valley...
At mid-levels, a subtle shortwave trough will move eastward across
the northern Plains this evening. At the surface, a low will move
eastward into eastern South Dakota as a cold front advances
southward across central and southern South Dakota. The front will
provide a focus for convective development this evening, although
scattered storms are also expected across parts of the post-frontal
airmass. Surface dewpoints over most of South Dakota are in the 60s
F, with lower to mid 70s F over south-central Minnesota. Along and
near the moist axis, the RAP has MLCAPE ranging from 2500 J/kg near
Rapid City to just above 3500 J/kg in far eastern South Dakota.
Short-term model forecasts suggest that a cluster of strong to
severe storms will develop near the instability axis early this
evening and grow upscale, tracking eastward across eastern South
Dakota into south-central Minnesota. Within this corridor, moderate
deep-layer shear and steep lapse rates will be favorable for a
severe threat...see MCD 1536. Any short line segment that can become
organized will likely be capable of severe wind gusts and hail.
There will be potential for wind gusts above 75 mph with any line
segment that can become robust.
Further west into parts of the northern High Plains, an axis of
moderate instability is analyzed by the RAP from near Rapid City
northwestward into southeastern Montana. A cluster of strong to
severe storms is expected to develop this evening and move
southeastward along this axis of instability. Moderate deep-layer
shear and steep mid-level lapse rates will support supercells
capable of isolated large hail and severe wind gusts. As convective
coverage increases, a potential for severe wind gusts is also
expected with any short line segment that can become intense...see
MCD 1535.
..Broyles.. 07/08/2026
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SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0419 PM CDT Tue Jul 07 2026
Valid 091200Z - 151200Z
...Synopsis...
This week exhibits a critical fire weather pattern for portions of
the Intermountain West with thunderstorms followed by dry and breezy
conditions later in the week, generating a favorable environment for
the emergence of possible holdover lightning ignitions. An
upper-level trough will move into southwest Canada Day
2-3/Wednesday-Thursday, with zonal westerly flow and a flattened
ridge over the northern half to two-thirds of the West. A weak dry
cold front will push through the Northwest and into the Great Basin
on Day 3/Thursday, with residual moisture and above normal
temperatures ahead of it. Moisture will push east of the Colorado
Rockies and be suppressed southward to southern Arizona and New
Mexico beyond Day 4/Friday as a ridge builds across the western
CONUS. Forecast uncertainty exists late in the period regarding how
an upper-level trough off the Pacific Northwest coast will interact
with the likely building upper-level ridge over most of the West,
especially the Intermountain West Day 6/Sunday and beyond. Some
ensembles do indicate thunderstorm potential early next week across
portions of central CA and the Sierra Nevada, where fuels will
continue to dry out this weekend out under hot and dry conditions.
Guidance will be monitored closely for dry thunderstorm
probabilities in future outlook cycles.
...Days 3-5/Thursday-Saturday...
Dry and breezy conditions continue on Day 3/Thursday across the
southern Great Basin into the Four Corners. Following several days
of mixed wet/dry thunderstorms, these conditions could promote the
emergence of any holdover lightning ignitions. Some residual
mid-level moisture could promote a few daytime isolated showers over
the eastern Great Basin and northwestern CO, though decreased
instability (compared to previous days) precludes dry thunderstorm
probabilities. An upper-level ridge will build across the
western/central CONUS later this week, amplifying through the
weekend. Meanwhile, upper troughing should persist over the Pacific
Northwest, further enhancing southwesterly flow aloft and dry
downslope flow over the northern Sierra Nevada into the southern
Cascades. 40% Critical probabilities have been maintained on Day
4-5/Friday-Saturday where guidance depicts dry and windy conditions
atop dry fuels. The spatial extent of drawn probabilities may be
adjusted in future outlooks as extended guidance becomes better
resolved.
..Elizalde-Garcia.. 07/07/2026
...Please see www.spc.noaa.gov/fire for graphic product...
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