RSS Mesoscale Discussions from Storm Prediction Center
No watches are valid as of Mon Jul 13 23:31:02 UTC 2026.
No Mesoscale Discussions are in effect as of Mon Jul 13 23:31:02 UTC 2026.
SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0233 PM CDT Mon Jul 13 2026
Valid 132000Z - 141200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER PARTS OF
CENTRAL MONTANA...SOUTHERN INTO CENTRAL ARIZONA...AND THE FLORIDA
PENINSULA INTO EXTREME SOUTHERN SOUTH CAROLINA...
...SUMMARY...
Thunderstorms with isolated strong to severe winds are still
possible this afternoon and evening across parts of the Southeast,
southern into central Arizona, and Montana.
...20Z Update...
The previous forecast (see below) remains unchanged, with only minor
changes made to the thunder/severe probabilities to reflect the
latest observations and guidance consensus.
..Squitieri.. 07/13/2026
.PREV DISCUSSION... /ISSUED 1101 AM CDT Mon Jul 13 2026/
An expansive upper ridge over the northern Plains will dominate the
weather across the US today, with only small areas of risk of severe
storms.
...FL/GA...
A hot and humid air mass is present today over the FL Peninsula into
parts of southeast GA/SC. Scattered afternoon thunderstorms are
expected to form in this regime, with the strongest cells capable of
gusty/damaging winds.
...AZ...
Widespread convection yesterday has resulted in a moist boundary
layer across southern AZ, where strong heating will occur again
today. This will lead to another round of scattered storms moving
off the higher terrain of eastern AZ and speading westward into the
Deserts. A few of the storms may produce gusty/damaging winds.
...MT...
Morning CAM solutions are consistent on the forecast of a cluster of
high-based thunderstorms forming over the mountains of southern MT
and tracking north-northeastward during the evening. Forecast
soundings would support some risk of a gusty/damaging winds in these
storms.
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SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0229 PM CDT Mon Jul 13 2026
Valid 151200Z - 161200Z
...NO SEVERE THUNDERSTORM AREAS FORECAST...
...SUMMARY...
The potential for organized severe storms continues to appear low on
Wednesday.
...Synopsis...
An expansive ridge will be present across the CONUS on Wednesday.
Upper-level troughs will be present near the Northwest coast and in
the Northeast, however. A few stronger storms will be possible
within western and central Montana, though repeated convection on
previous days will likely lead to cooler temperatures and uncertain
storm intensity. While there still is some uncertainty to the track
of the upper trough off the Northwest coast, some potential exists
for gusty outflow wind in central/eastern Oregon. Across parts of
the Mid-Atlantic, a moist and unstable airmass will be present south
of a surface boundary. Subtle mid-level height falls may be enough
to initiate isolated thunderstorms. However, there is also potential
for the environment to stay capped. The environment would support
damaging winds if storms can form.
..Wendt.. 07/13/2026
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SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0232 PM CDT Mon Jul 13 2026
Valid 141200Z - 151200Z
...Afternoon Update...
The Isolated Dry Thunderstorm risk area was expanded into portions
of the Klamath-Siskiyou region and Northern Coast Ranges of
California for Day 2/Tuesday. Forecast soundings depict deep
inverted-V profiles, sufficient afternoon MUCAPE values of 100-300
J/kg, PWATs less than 0.8", and fast LCL-EL mean winds of over 25
kts, warranting the expansion of highlights. The rest of the
forecast remains on track, see the previous discussion for more
information.
..Elizalde-Garcia.. 07/13/2026
.PREV DISCUSSION... /ISSUED 0152 AM CDT Mon Jul 13 2026/
...Synopsis...
Much of the Continental US will experience strong mid-level ridging
on Tuesday. Northward transport of monsoonal moisture along the
western periphery of the ridge will result in isolated dry
thunderstorms over portions of the Pacific Northwest, and dry and
breezy conditions across the northern High Plains will result in
Elevated fire-weather concerns.
...Northern High Plains...
In response to a developing surface low in eastern Montana,
east-southeasterly winds of 15-20 MPH are anticipated across the
northern High Plains into central Wyoming. Combined with widespread
relative humidity near 10-15% and critically receptive fuels, at
least Elevated fire-weather concerns are forecast for Tuesday
afternoon.
...Southern and Central Oregon into portions of northeastern
California and northwestern Nevada...
Northward transport of monsoonal moisture along the periphery of the
mid-level ridge will bring more isolated dry thunderstorms to
portions of the Pacific Northwest on Tuesday. HREF/REFS calibrated
thunder guidance shows convective activity occurring with
precipitable water content of 0.75-1.0", suggesting a mix of wet and
dry thunderstorms. However, forecast sounding profiles show deep
inverted-Vs and LCL-EL mean wind speeds of 25-30 kts indicate
limited precipitation efficiency. Given fuels guidance showing ERCs
in the 80th-90th annual percentile range, lightning-based ignitions
will be possible.
...Please see www.spc.noaa.gov/fire for graphic product...
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SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0354 PM CDT Mon Jul 13 2026
Valid 151200Z - 211200Z
...Synopsis...
A strong upper high will persist over the central/northern Plains
through the end of this week into the early weekend. Upper-level
troughing will continue near and off the Pacific Northwest coast
with monsoonal moisture streaming northward across much of the
Intermountain West this week; meanwhile, daily monsoonal
thunderstorms are likely across the Southwest into the Great Basin.
An upper-level trough is forecast to move near/into the Pacific
Northwest early Day 4/Thursday, potentially suppressing moisture
south and eastward. However, model spread and ambiguity in the
spatial extent/strength of troughing yields significant uncertainty
in the progression of the upper pattern across the West. Farther
east, a deep upper-level trough is expected to weaken the ridge over
the Great Lakes and Northeast as it digs southward on Days
2-3/Tuesday-Wednesday, leading to unsettled conditions across the
region through the remainder of the forecast period.
...Central to northern High Plains...
Hot, dry, and breezy conditions are likely across portions of
eastern Wyoming, western South Dakota, western Nebraska and eastern
Colorado on Day 3/Wednesday through at least Day 4/Thursday. While
RH is expected to recover overnight, south-southeast winds are
likely to remain breezy amid dry fuels and hot daytime temperatures.
40% Critical probabilities have been maintained; however, may need
to be confined in future outlooks as predictability increases in the
evolution of the upper pattern.
...Portions of northeastern California and the Central Valley,
western Great Basin, and far south-central Oregon...
Warm daytime temperatures and low RH will contribute to drying fuels
across the California Coastal Ranges into the Central Valley. ERCs
are forecast to approach the 90-95th percentile mid-late week amid
dry and breezy conditions, supporting any new ignitions and the
emergence of lightning holdovers from wet/dry thunderstorms early in
the forecast period. 40% Critical probabilities remain on Days
3-4/Wednesday-Thursday to account for this threat. Farther north,
guidance has backed off on the timing of stronger winds overlapping
low RH, resulting in 40% Critical probabilities being removed on Day
3/Wednesday across northeastern California and adjacent areas. Yet,
the potential for stronger flow amid a returning dry airmass on Day
4/Thursday warrants the introduction of 40% Critical probabilities.
..Elizalde-Garcia.. 07/13/2026
...Please see www.spc.noaa.gov/fire for graphic product...
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