SPC AC 260100
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0800 PM CDT Sat Jul 25 2026
Valid 260100Z - 261200Z
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR EASTERN
SD...SOUTHWEST MN...NORTHERN IA...
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF
CENTRAL/EASTERN MT...
...SUMMARY...
Severe gusts (potentially greater than 75 mph) remain possible this
evening from eastern South Dakota into northern Iowa and southwest
Minnesota. Isolated to widely scattered severe gusts also remain
possible across parts of Montana.
...SD into southern MN/northern IA/far northeast NE...
A loosely organized storm cluster is moving across eastern SD this
evening. Additional intensification remains possible this evening,
as this cluster encounters extreme downstream buoyancy, with MLCAPE
of 4000-5000 J/kg within a very moist (dewpoints around 80 F)
environment. The ongoing cluster has produced measured gusts of
60-80 mph, so any notable intensification could lead to an increase
in potential for gusts in the 75-90 mph range. Isolated hail and
perhaps a tornado also remain possible through dusk with this
cluster. Increasing CINH with time and eastward extent should
eventually result in a weakening trend later tonight, though an
organized severe threat could eventually approach parts of southeast
MN/northeast IA into northwest IL overnight.
Farther northwest, a separate storm cluster is moving across
north-central SD, within a similarly favorable environment. In the
short term, this cluster may continue to move east-southeastward
along a surface boundary with a continued severe-wind threat.
Eventually, weakening buoyancy in the wake of the southeast SD
cluster will tend to result in a weakening trend with this cluster.
...Central/eastern Montana...
Strong to locally severe storms may persist through dusk across
parts of central/eastern MT, within a well-mixed environment that is
favorable for severe-wind potential. Increasing CINH will result in
an eventual weakening trend later tonight, though remnant outflows
may still produce strong to locally severe gusts as storms diminish.
...Southern AZ...
Widely scattered storms and increasing outflow may continue to
support strong to localized severe gusts within a very hot and
well-mixed environment across parts of southern AZ. Weak deep-layer
flow/shear should keep any remaining threat generally disorganized.
..Dean.. 07/26/2026
NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 0600Z
SPC AC 251719
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1219 PM CDT Sat Jul 25 2026
Valid 261200Z - 271200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE MID
MISSOURI VALLEY ACROSS THE UPPER MISSISSIPPI VALLEY AND WESTERN
GREAT LAKES...
...SUMMARY...
Severe thunderstorms capable of large hail and damaging winds are
possible from the upper Mississippi Valley and Great Lakes into
portions of the mid Missouri Valley on Sunday and Sunday night.
...From eastern SD and NE to the Upper Great Lakes...
The forecast continues to have major uncertainties regarding
placement of the most likely severe storm corridors, with a wide
range of model solutions. In general, the most likely threat areas
include northern MN into WI and Upper MI, on the periphery of the
upper ridge and where stronger winds aloft will exist coincident
with strong instability, and from southeast SD into northeast NE
within a super-heated surface trough.
Beneath 40-50 kt midlevel northwesterlies, areas of strong
instability will develop with relatively steep midlevel lapse rates
and 70s F dewpoints, from parts of MN into WI. Models suggest
various storm clusters are possible late in the day, and these would
travel quickly southeastward with damaging wind and hail likely.
Some severe activity could potentially push south of the Slight Risk
area into more of northern IL, IN, and Lower MI. However, the
instability gradient will be a limiting factor for eastward extent.
Clusters of storms, possibly forming into a small MCS, are also
expected where very hot temperatures develop into SD. The deeply
mixed boundary layer combined with surface convergence within the
low pressure trough will support afternoon development over eastern
SD, with a corridor of damaging wind potential extending
southeastward into eastern NE and western IA.
...SC and GA...
Daytime heating of a high PWAT air mass will lead to moderate
instability during the afternoon. A surface trough will deepen over
the central Carolinas and into eastern GA, with an uncapped air mass
and weak convergence yielding scattered storms. Shear will be weak,
but modest northwest flow aloft should support corridors of damaging
wind gusts as storms develop southeastward toward the coast.
..Jewell.. 07/25/2026
WUUS02 PTSDY2
NOTE: THE NEXT DAY 2 OUTLOOK IS SCHEDULED BY 0600Z
SPC AC 251925
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0225 PM CDT Sat Jul 25 2026
Valid 271200Z - 281200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PARTS OF THE
GREAT LAKES INTO THE OHIO VALLEY...
...SUMMARY...
Severe storms capable of damaging winds and large hail are possible
across the Great Lakes into the Ohio Valley Monday into Monday
night.
...Great Lakes to Ohio Valley...
A large upper ridge will hold over the Rockies and into the Plains,
with a moderate northwest flow regime from the Upper MS Valley and
Great Lakes into the OH Valley/Appalachians. While embedded
perturbations will exist during the day, the most prominent height
falls will occur Monday night over the Great Lakes.
At the surface, low pressure will develop late in the day from WI
into Lower MI, with a cold front pushing south overnight trailing
southwestward into northern IL. A moist and unstable air mass will
redevelop and push eastward across the region late in the day and
overnight as 850 mb winds near 40 kt develop out of the west.
Some ongoing activity may be present from Upper MI into WI, and this
could either persist or strengthen during the day as the system
develops southeastward. Deep-layer shear of 40-50 kt along with the
strong instability could support a southward-moving MCS capable of
damaging winds, perhaps with significant gusts. Will maintain
current Slight Risk due to uncertainty, but higher probabilities
could be needed in later outlooks.
...Eastern WY into western NE...
Beneath the upper ridge, eastern low-level winds in a post frontal
regime will aid westward moistening, with marginal instability. A
deep mixed boundary layer will favor damaging wind gusts with
activity that develops in the uncapped air mass during the late
afternoon. Modest westerlies aloft and weak low-level easterlies
should favor southeastward-moving storms with locally severe outflow
winds.
..Jewell.. 07/25/2026
WUUS03 PTSDY3
NOTE: THE NEXT DAY 3 OUTLOOK IS SCHEDULED BY 0730Z
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