RSS Mesoscale Discussions from Storm Prediction Center
No watches are valid as of Fri Jul 24 08:42:01 UTC 2026.
No Mesoscale Discussions are in effect as of Fri Jul 24 08:42:01 UTC 2026.
SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1229 AM CDT Fri Jul 24 2026
Valid 241200Z - 251200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR
CENTRAL/EASTERN ND INTO PARTS OF NORTHERN MN...
...SUMMARY...
Severe thunderstorms capable of large to very large hail, damaging
wind, and possibly a tornado are forecast during the afternoon and
evening across portions of North Dakota into northern Minnesota.
...Dakotas into northern MN...
Within an amplifying upper-level pattern, multiple low-amplitude
midlevel shortwave troughs are forecast to move east-southeastward
from the northern Rockies toward ND and northern MN through the
period. A surface trough will trail southwestward from a deep
surface cyclone that will move from northern MB/ON towards Hudson
Bay. A plume of relatively steep midlevel lapse rates will
overspread a warm and moist boundary layer along/east of the surface
trough, with MLCAPE increasing above 2000 J/kg across parts of ND
into northwest MN by late afternoon. Strengthening mid/upper-level
west-northwesterly flow will result in favorable deep-layer shear,
resulting in a conditionally favorable environment for severe
storms.
Guidance generally suggests that widely scattered storms will
develop along the surface trough by late afternoon across eastern
ND. Elongated hodographs and favorable instability will initially
favor supercell development, though some clustering will be possible
with time into the evening. Large to very large hail will be the
primary initial hazard. Some tornado potential could evolve with
persistent supercells, as low-level shear gradually increases from
late afternoon into the evening. Any organized clustering could
result in localized corridors of greater severe-wind potential. Some
severe threat could persist as storms move into a larger portion of
northern/central MN through late evening, with a general weakening
trend expected late in the period due to increasing CINH and
weakening buoyancy.
Farther northwest, some guidance depicts isolated supercell
development west of the surface trough across the Canadian Prairies
during the late afternoon, which could then move into parts of
northern/central ND within a northwesterly flow regime. This
scenario is more uncertain, but 5% wind/hail probabilities have been
expanded westward in response to this potential.
...Coastal Carolinas vicinity...
Relatively strong heating of a richly moist airmass (PW above 2
inches) will result in the development of moderate buoyancy across
parts of the Coastal Carolinas and southeast GA, in the vicinity of
a surface front. Scattered storm development is expected by
early/mid afternoon. Deep-layer flow will generally be weak, but
locally damaging downbursts and outflow winds will be possible
within the warm and very moist environment.
...Southern High Plains vicinity...
A nearly stationary front draped from eastern NM into the TX/OK
Panhandles is expected to become a focus for thunderstorm
development by late afternoon or early evening. Buoyancy is forecast
to remain modest, and deep-layer flow will be weak, so organized
storm potential currently appears low. However, strong
boundary-layer heating/mixing will support potential for localized
downbursts. While magnitude and coverage of the threat currently
appear rather limited, wind probabilities may eventually be needed,
if confidence increases in more than very localized severe-wind
potential.
...Parts of the Great Basin into the Northern Rockies...
Widely scattered high-based storm development is expected this
afternoon from parts of the Great Basin into the northern Rockies,
along the periphery of an amplifying upper ridge over the Four
Corners region. Buoyancy and deep-layer shear are both expected to
remain weak, but strong to locally severe gusts will be possible
within the hot and well-mixed regime. Wind probabilities may
eventually be needed, if confidence increases in more than a very
localized/transient severe-gust threat.
..Dean/Jirak.. 07/24/2026
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SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1219 AM CDT Fri Jul 24 2026
Valid 251200Z - 261200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE
NORTHERN ROCKIES INTO THE UPPER MIDWEST...AND ACROSS PORTIONS OF
SOUTHEAST ARIZONA...
...SUMMARY...
Isolated severe storms will be possible from the northern Rockies
into the upper Midwest, and across portions of southeast Arizona.
...Synopsis...
A prominent mid-level ridge will remain anchored over central North
America with the amplification of a downstream trough across the
eastern CONUS. At the surface, ridging will be maintained over the
Northeast with a weak front along the Southeast coastal areas. That
boundary will extend northwest to low pressure over the northern and
central Plains.
...Northern Rockies...
Forcing for ascent associated with a subtle short-wave trough
cresting the ridge axis will combine with heating along the high
terrain to foster widely scattered thunderstorm development Saturday
afternoon. Area forecast soundings exhibit steep low/mid-level lapse
rates, a deeply mixed boundary layer, and MLCAPE approaching 1000
J/kg. Moreover, some enhancement of mid-level flow and resultant
vertical shear is forecast, which may support some storm
organization with the primary hazard being isolated severe wind
gusts.
...South Dakota into the upper Midwest...
Cyclogenesis is forecast over western SD along a weak front
extending from central MT into MN/WI. The air mass along and south
of the boundary in SD is expected to become quite hot with
temperatures of 100-110. And while moisture will remain limited, the
presence of steep low/mid-level lapse rates will largely contribute
to modest instability during the peak of the diurnal heating cycle.
Isolated storm development is expected by afternoon into early
evening near and south of the front atop the hot, well-mixed
boundary layer with latent cooling processes in the sub-cloud layer
potentially leading to severe outflow winds.
Farther east into MN and WI, a significantly more moist boundary
layer is expected in the vicinity of the front, yielding a
moderately to strongly unstable air mass by afternoon. However,
notable height rises are forecast with the expansion of the upper
ridge into the region, leading to uncertainty in whether
surface-based storms will develop due to the strengthening cap. On
the condition that storms develop and become sustained, seasonably
strong vertical shear will exist to support supercells with the
primary hazard being large hail. Low hail and wind probabilities
have been included in this forecast to acknowledge the conditional
threat.
Saturday night into early Sunday, there is some model signal for
elevated storm development along the nocturnal low-level jet. In
that scenario, sufficient instability and vertical shear are
expected to exist to support some severe weather risk.
...Southeast Arizona...
A slight enhancement of easterly mid-level flow is forecast across
the region, atop a modestly unstable, but steep-lapse-rate
environment. Widely scattered thunderstorms are expected to develop
over the Gila Mountains and adjacent high terrain by afternoon with
a subsequent movement toward the lower desert floor. Some cold pool
organization is possible in areas of storm clustering with an
associated risk for locally severe wind gusts.
..Mead.. 07/24/2026
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SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0207 AM CDT Fri Jul 24 2026
Valid 261200Z - 271200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER THE UPPER
MISSISSIPPI VALLEY INTO UPPER MIDWEST...
...SUMMARY...
Severe thunderstorms capable of mainly large hail and damaging winds
are possible from the upper Mississippi Valley and Great Lakes into
portions of the Ohio and mid Missouri Valleys on Sunday and Sunday
night.
...Synopsis...
Along the periphery of an upper high anchored over the central and
southern Plains, a belt of enhanced mid-level winds will extend from
the Pacific Northwest through south-central Canada into the Great
Lakes. A series of perturbations will be embedded within the
higher-momentum flow regime, the most notable being a disturbance
tracking through southern parts of SK and MB into northwest ON and
northern MN late Sunday night. A surface low is forecast to follow
that same track with an associated trough or weak cool front
advancing through the northern Plains into the upper MS Valley.
...Upper Mississippi Valley into the Great Lakes...
Boundary-layer dewpoints in the 60s to mid 70s will coincide with an
eastward-expanding EML plume and associated cap to yield a fairly
widespread reservoir of moderate to strong instability across the
region on Sunday. There is some model signal for a subtle mid-level
disturbance to progress from the northern Plains into the upper
Midwest during the day with an associated band of forcing for ascent
potentially serving as a focus for diurnally enhanced thunderstorm
development. However, the absence of discernible surface boundaries
and the residual capping leads to uncertainty in the location and
extent of diurnally enhanced thunderstorm development. Nonetheless,
a conditional severe weather threat will exist with any storms that
can become rooted within the boundary layer, given the presence of
35-50 kt deep-layer shear.
More substantial forcing for ascent is forecast Sunday evening into
night across the upper MS Valley with the approach of the mid-level
wave mentioned in the synopsis. At that time, the surface front will
be moving into the area from the west, potentially serving as a
focus for thunderstorm development. The 00Z ECMWF in particular
depicts a large thunderstorm complex developing over that area with
a subsequent southward movement toward the mid MO Valley Sunday
night into early Monday. A corridor of enhanced damaging wind
potential would exist in that scenario; however, confidence in such
an occurrence is presently too low to include higher probabilities
and a conditional intensity group 1 contour.
..Mead.. 07/24/2026
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Day 4-8 Outlook
Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0337 AM CDT Fri Jul 24 2026
Valid 271200Z - 011200Z
...DISCUSSION...
...Day 4/Monday...
A prominent upper high will remain centered over the central and
southern Plains with a belt of enhanced mid-level flow forecast
along the periphery of that feature from the northern Plains into
the Great Lakes. Within that flow regime, a short-wave trough is
forecast to translate through the Great Lakes in tandem with a
surface low and trailing cold front. A hot and moist boundary layer
is expected ahead of the front, yielding moderate to strong
instability by afternoon. Despite veered low-level winds,
strengthening mid/upper-level winds in the exit region of a jet
streak will contribute to sufficient vertical shear for organized
severe storms across portions of the Great Lakes into the OH Valley
Monday afternoon into night.
...Day 5/Tuesday...
The Day 4/Monday short-wave trough is forecast to evolve into an
upper low across southwest ON and the lower Great Lakes with an
associated belt of stronger cyclonic flow developing from the OH
Valley into the southern Mid-Atlantic and NC. At the surface, an
area of low pressure will develop from the lower Great Lakes into
central NY with a trailing cold front advancing through the upper OH
Valley, central Appalachians, and Mid-Atlantic.
Thunderstorms may be ongoing Tuesday morning along and ahead of the
front from the lower Great Lakes and upper OH Valley into the
Mid-Atlantic. Stronger heating is anticipated to the south of the
early-day storms from the southern Mid-Atlantic into NC, where
moderate to potentially strong instability is forecast. The
strongest instability will coincide with modestly strong deep-layer
shear to support some severe weather threat in those areas Tuesday
afternoon and evening.
...Days 6-8/Wednesday-Friday...
The 00Z ensemble means depict a slight westward regression of the
dominant mid/upper-level high with persistent troughing along the
East Coast. On the periphery of the high, a notable short-wave
trough is forecast to progress from the Canadian Rockies on
Wednesday through the Prairie Provinces on Thursday with modest
height falls along the international border. By Friday, there is
some model signal for another short-wave trough to move into the
upper MS Valley and Great Lakes regions. At the surface, a more
substantial cold front is projected to move into the northern Plains
on Thursday, and the upper Midwest and Great Lakes by Friday.
A few severe storms appear possible in the Southeast and northern
Plains on Wednesday, the northern Plains on Thursday, and the upper
Midwest into the Great Lakes on Friday. Confidence in the magnitude
and areal extent of the threat is currently too low to delineate
additional areas.
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SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0156 AM CDT Fri Jul 24 2026
Valid 241200Z - 251200Z
...CRITICAL FIRE WEATHER AREA FOR NORTHEASTERN
CALIFORNIA...NORTHWESTERN NEVADA...AND SOUTH-CENTRAL/SOUTHEASTERN
OREGON...
...Synopsis...
As an upper-level trough approaches the Pacific Northwest coast
today, a series of disturbances cresting the upper-level ridge over
the West will result in increased flow aloft from the Pacific
Northwest into the northern Plains. Given the hot and dry airmass in
place over much of the region, deep boundary-layer mixing will
promote gusty surface winds raising fire-weather concerns in an
increasingly favorable fuelscape.
...Northeastern California...Northwestern
Nevada...South-Central/Southeastern Oregon...
Very hot and dry conditions will result in multiple hours of
single-digit RH values across the region. With enhanced
southwesterly flow aloft brushing the area, deep vertical mixing
will result in west-southwesterly surface winds approaching 20 mph.
Given the dry fuels (ERC values exceeding the 80th percentile) and
recent lightning events with limited rainfall, critical fire weather
conditions are likely.
...Northern Montana...
Very strong winds aloft and a deep, well-mixed boundary layer will
result in sustained afternoon westerly surface winds approaching 20
mph in the presence of RH values dipping just below 15%. These
elevated conditions will cure the fuels for the coming days.
..Jirak.. 07/24/2026
...Please see www.spc.noaa.gov/fire for graphic product...
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SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0157 AM CDT Fri Jul 24 2026
Valid 251200Z - 261200Z
...CRITICAL FIRE WEATHER AREA FOR EASTERN OREGON/WASHINGTON AND
ADJACENT PORTIONS OF CALIFORNIA...NEVADA...IDAHO...AND MONTANA...
...Synopsis...
Continued upper-level ridging over the West on Saturday with
enhanced flow over the ridge will result in an expansive area of
fire-weather concerns, extending from northern California/Nevada
into eastern Oregon/Washington and northern Idaho/Montana.
...Critical Fire Weather Conditions...
Successive days with hot, dry, and breezy conditions warrant
critical fire-weather highlights in a favorable fuelscape,
characterized by ERC values largely ranging from the 80th-95th
percentiles across the region. Deep, well-mixed boundary layers are
likely to yield critical RH values (<15%) and sustained afternoon
wind speeds exceeding 20 mph. The most favorable meteorological
conditions are likely across southeastern Oregon.
...Dry Thunderstorm Potential...
While PW values around one inch may favor wetting rains from
thunderstorms across central/eastern Montana, very hot and deep
boundary layers will promote precipitation evaporation. When
considering relative fast storm motions (25-30 mph), a mix of wet
and dry thunderstorms is possible across the region.
..Jirak.. 07/24/2026
...Please see www.spc.noaa.gov/fire for graphic product...
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