RSS Mesoscale Discussions from Storm Prediction Center
No watches are valid as of Wed Jul 22 10:05:02 UTC 2026.
No Mesoscale Discussions are in effect as of Wed Jul 22 10:05:02 UTC 2026.
SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1250 AM CDT Wed Jul 22 2026
Valid 221200Z - 231200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE
SOUTHERN MID-ATLANTIC...
...SUMMARY...
Isolated to scattered storms are possible in the southern
Mid-Atlantic into New England this afternoon/evening. Damaging winds
are the primary concern. Isolated strong to severe wind gusts are
also possible in the central High Plains and central Oregon.
...Synopsis...
A upper trough will persist in the Northeast CONUS with a ridge
amplifying into the Northwest. An offshore upper low in the
Northwest will eject shortwave perturbations into Oregon/Washington.
At the surface, a cold front will move through New England. The
front will slow in the Mid-Atlantic during the afternoon before
moving southeast during the overnight.
...Mid-Atlantic into parts of Carolinas...
The cold front in this region is expected to slow/stall near the
Blue Ridge into eastern Maryland. Models suggest
clouds/precipitation will be likely in the vicinity of the
Virginia/North Carolina border. Mid-level forcing for ascent will be
weak at best and subtle mid-level warming is expected from far
southern Virginia into the Carolinas. Moderate to strong mid-level
winds will be in place with the strongest flow in Virginia/Maryland.
It is not clear how convection will evolve during the day/afternoon.
Storms could potentially continue from the morning into the
afternoon over portions of the region. There also is potential for
storms to develop along the cold front where there could potentially
be greater surface heating. In the Carolinas, the lack of ascent and
cloud cover concerns limit confidence in how many storms and how
strong they will become. Greater confidence in storm coverage exists
in Virginia into the DelMarVa where the Slight Risk has been
maintained. The kinematic environment will support occasionally
organized storms capable of damaging winds and perhaps a tornado or
two.
...New England...
A strong mid-level jet will be favorably timed during the afternoon,
particularly for New Hampshire/Maine. As the cold front moves
through, scattered storms appear probable. Effective shear of 30-40
kt and strong upper-level winds will promote supercell structures.
The shear vector will have a large component parallel to the
north-south cold front so it is not clear how long discrete
structures can be maintained. Isolated damaging winds, marginally
severe hail, and perhaps a tornado would be possible. Some
consideration was given to a higher severe probabilities, but the
region will initially be in the wake of a shortwave trough and
thermodynamic profiles exhibit characteristics (e.g., mid-level
inversion, lowered equilibrium level) that limits confidence in how
many severe-caliber storms will exist.
Farther south and west, there is less signal for convective
development along the cold front. A Marginal risk has been
maintained this outlook cycle. Some risk for damaging winds would
exist if an isolated storm can develop along the front.
...Central High Plains...
Southeasterly surface winds will combine with increasingly
westerly/northwesterly flow aloft to promote modest deep-layer shear
(around 30 kt 0-6 km) during the afternoon/evening. The development
of a weak lee low and low-level moisture moving northwest around the
Midwest anticyclone will aid in storm development within the region.
Temperature-dewpoint spreads at the surface will allow for efficient
outflow production. A strengthening southeasterly low-level jet in
western Kansas may also help maintain convection farther east during
the evening. Severe wind gusts are possible with this activity.
...Oregon...
An upper-low will be positioned off the Northwest Coast. Subtle
ascent will help to initiate storms in parts of central Oregon
during the afternoon. Models are in strong agreement that scattered
storms will move northward into at least early evening. Strong
heating will lead to large temperature-dewpoint spreads at the
surface. Inverted-v thermodynamic profiles will promote a risk for
strong to severe wind gusts despite limited buoyancy and shear.
..Wendt/Weinman.. 07/22/2026
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SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1220 AM CDT Wed Jul 22 2026
Valid 231200Z - 241200Z
...NO SEVERE THUNDERSTORM AREAS FORECAST...
...SUMMARY...
Severe thunderstorm potential appears low on Thursday. However,
locally gusty winds could occur with thunderstorms across the
central High Plains.
...Discussion...
In the mean, an amplified upper ridge will persist across he West,
with the subtropical high over TX shifting west toward the Four
Corners vicinity through the period. An upper shortwave trough
embedded within the eastern periphery of the upper ridge will
migrate southeast from the central Rockies to the Mid/Lower MO
Valley through early Friday morning.
Southerly low-level flow across the Plains will result in a belt of
modest boundary-layer moisture across the central High Plains. Steep
midlevel lapse rates will foster weak instability across parts of
WY/CO into western KS. Scattered thunderstorms will develop during
the afternoon and spread east/southeast across the central High
Plains. A deeply mixed boundary layer will support isolated strong
outflow gusts. However, weak vertical shear and limited instability
will preclude severe probabilities at this time.
..Leitman.. 07/22/2026
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SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0106 AM CDT Wed Jul 22 2026
Valid 241200Z - 251200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
EASTERN NORTH DAKOTA AND NORTHERN MINNESOTA...
...SUMMARY...
Isolated severe thunderstorms are possible on Friday across portions
of eastern North Dakota into northern Minnesota.
...North Dakota/Minnesota...
An upper shortwave trough will develop southeast from the Canadian
Prairies toward the Great Lakes on Friday. This will result in some
enhancement of northwesterly flow aloft across the region. At the
surface, low pressure will move from northern Manitoba into Quebec
and a trailing cold front will drop southeast across ND and
northern MN. Southerly low-level flow ahead of the front will
transport low to mid 60s F dewpoints across parts of the eastern
Dakotas and MN. A plume of steepening midlevel lapse rates will
overspread the region, supporting 1000-2000 J/kg MLCAPE. Vertically
veering wind profiles, with 30-50 kt northwesterly flow between
700-500 mb will support effective shear magnitudes greater than 40
kt. Isolated thunderstorms are expected to develop by late
afternoon/early evening near the surface front. Wind profiles
suggest supercells will be possible. Forecast soundings indicate
some areas may maintain weak to moderate capping, which may preclude
surface-based convection. However, elevated storms will pose a risk
for isolated large hail. If thunderstorms are surface-based, a risk
for strong gusts and tornado would also be possible.
..Leitman.. 07/22/2026
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Day 4-8 Outlook
Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0226 AM CDT Wed Jul 22 2026
Valid 251200Z - 301200Z
...DISCUSSION...
...Upper Midwest to Ohio Valley and Mid-Atlantic...
An upper ridge centered over the High Plains will persist through
the middle of next week. Meanwhile, upper troughing will be
maintained over the eastern U.S. Periods of enhanced northwesterly
flow aloft are expected across parts of the Upper Midwest/Great
Lakes into parts of the Ohio Valley and Mid-Atlantic on the eastern
periphery of the Plains upper ridge. Several shortwave impulses are
forecast to develop southeast from Canada within this northwest flow
regime. This could support daily severe thunderstorm chances from
the Upper Midwest into the Ohio Valley, and possibly the
Mid-Atlantic. However, the timing of these features is uncertain,
and midlevel capping could limit the spatial extent of severe
potential. It is likely that portions of the Upper Midwest into the
Ohio Valley will need severe probabilities in later outlooks,
particularly for Day 4-6/Sat-Mon, and possibly the mid-Atlantic by
Day 7/Tue. However, confidence in where this risk will develop each
day is too low for 15 percent delineation at this time.
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