RSS Mesoscale Discussions from Storm Prediction Center
No watches are valid as of Sat Jul 11 07:31:01 UTC 2026.
No Mesoscale Discussions are in effect as of Sat Jul 11 07:31:01 UTC 2026.
SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1257 AM CDT Sat Jul 11 2026
Valid 111200Z - 121200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PARTS OF THE
OZARKS INTO THE TENNESSEE VALLEY...AND IN SOUTHEAST ARIZONA...
...SUMMARY...
Thunderstorms with severe wind gusts will be possible today from
parts of Ozarks eastward into the mid Mississippi and Tennessee
Valleys. Severe wind gusts are also possible in southeast Arizona. A
few severe gusts may also occur in the southern Plains and from the
southern Appalachians to the Atlantic Seaboard.
...Mid Mississippi and Tennessee Valleys/Ozarks/Southern Plains...
A mid-level shortwave trough will move eastward into the mid
Mississippi Valley today. At the surface, a very moist airmass will
be in place from the Ozarks eastward into the Tennessee Valley,
where dewpoints will be in the 70s F. Low-level convergence is
expected to increase by early afternoon ahead of the shortwave
trough in the mid Mississippi Valley. This combined with large-scale
ascent ahead of the shortwave trough will support scattered
thunderstorm development in the afternoon from eastern Missouri into
southern Illinois and western Kentucky. Additional storms may
develop along an east-to-west axis of low-level convergence from far
northern Arkansas into western and middle Tennessee. As surface
temperatures warm today, MLCAPE is forecast to peak in the 2000 to
3000 J/kg range over much of this airmass, with 0-6 km shear in the
20 to 30 knot range. This, along with steep low-level lapse rates,
will be favorable for severe wind gusts with the stronger
multicells. The threat should be concentrated in the afternoon and
early evening.
Additional more isolated storms are expected to form this afternoon
from the Texas Panhandle eastward into Oklahoma. Moderate
instability and steep low-level lapse rates will support an isolated
threat for severe gusts, mainly in the late afternoon.
...Southeast Arizona...
A moist airmass will be in place over southern Arizona today with
surface dewpoints in the 50s F. As surface temperatures warm,
moderate instability will likely develop over much of southeastern
Arizona, where SBCAPE should peak in the 1000 to 2000 J/kg range.
Thunderstorms are expected to form along a north-to-south corridor
of low-level convergence near the Arizona and New Mexico state line,
with storms moving westward across southeast Arizona. At 00Z, RAP
forecast soundings have 0-6 km shear near 25 knots, with 0-3 km
lapse rates in the 8 to 9 C/km range. This environment will be
favorable for severe wind gusts with the stronger multicells,
especially if an organized line can develop.
...Southern Appalachians to Atlantic Seaboard...
A very moist airmass will be in place today from the southern
Appalachians eastward to the Atlantic Seaboard, where surface
dewpoints will be from the upper 60s to the mid 70s F. As surface
temperatures warm, moderate instability will develop over much of
the region. Thunderstorms that form in the higher terrain and along
zones of convergence will have potential for isolated severe gusts.
The threat will be concentrated in the late afternoon as instability
and low-level lapse rates become maximized.
..Broyles/Halbert.. 07/11/2026
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SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
0100 AM CDT Sat Jul 11 2026
Valid 121200Z - 131200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS EAST
GEORGIA INTO SOUTH CAROLINA...
...SUMMARY...
Scattered strong-to-severe thunderstorms capable of producing wind
damage will be possible across much of the Southeast on Sunday, with
the greatest potential across South Carolina. Additional
strong-to-severe thunderstorms will be possible across portions of
Arizona late Sunday afternoon into Sunday night.
... Synopsis ...
The center of an expansive mid-level ridge will build northeast from
the Northern Rockies into the Northern Plains on Sunday,
encompassing much of the contiguous US. A weak, positively-tilted
mid-level trough will slowly move southeast from the Ohio Valley
into the Tennessee Valley.
At the surface, a weak low will meander southeast underneath the
aforementioned mid-level trough. At the start of the forecast
period, a convectively augmented boundary will arc from this low
southwest into Arkansas before turning northwestward and extending
into south-central/south-west Kansas. This boundary will push south
through the period and serve as a focus for additional thunderstorm
development Sunday afternoon.
... Much of South Carolina into East Georgia ...
Ahead of the meandering surface low, a very warm and moist airmass
will once again be in place as surface temperatures warm into the
80Fs and 90Fs in the presence of surface dewpoint temperatures in
the 60Fs and low 70Fs. The result will be around 1000-2000 J/kg of
MUCAPE within a mostly uncapped environment. Scattered thunderstorms
should develop during the afternoon as convective temperatures are
breached. Weak mid-level flow (on the order of 15-20 knots) will
favor single cells and multicell clusters. Relatively steep
low-level lapse rates beneath the LCL and high precipitable water
values will support downbursts/outflow winds capable of damage.
Given the cooler mid-level temperatures associated with the
mid-level trough, a few marginally severe hail reports may also
occur.
... Southern High Plains into the Southeast ...
To the south of the previously mentioned surface boundary, a
warm/hot moist airmass will be in place as temperatures warm into
the 90Fs to near 100F with dewpoints in the 60Fs and 70Fs. This will
result in MUCAPE on the order of 2000 to perhaps 3000 J/kg. Strong
diurnal heating coupled with weak convergence along the surface
boundary should result in scattered thunderstorm development during
the afternoon. These storms will be capable of producing
strong-to-marginally severe convective outflow winds.
... Arizona ...
Steep mid-level lapse rates and ample mid-level moisture will
support scattered thunderstorm development during the afternoon.
This region will be to the south of the strong CONUS-wide ridge with
a belt of enhanced easterlies overhead. This should allow
thunderstorms that develop across the higher terrain of Arizona to
move west into the lower desert. A deeply mixed boundary layer will
allow for strong outflow winds to develop as convection spreads west
into southern and central Arizona.
... Upper Great Lakes ...
This region will be glanced by large-scale ascent associated with a
strengthening mid-level jet across central Canada. Surface
temperatures warming into the upper 80Fs and low 90Fs with dewpoints
temperatures in the mid 60Fs to perhaps 70Fs will result in strong
instability during the afternoon. Large-scale ascent will be modest
at best, but a few thunderstorms are expected to develop, perhaps
along a 700-millibar front/boundary, during the afternoon. Steep
low-level and mid-level lapse rates and effective-layer shear on the
order of 30-35 knots will support a few strong-to-severe wind gusts
and perhaps marginally severe hail. Forecast hodographs have modest
curvature in the low-levels that a tornado or two may be possible
with any supercell that can sustain itself and move more southerly,
realizing the totality of the low-level curvature.
..Marsh.. 07/11/2026
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SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0228 AM CDT Sat Jul 11 2026
Valid 131200Z - 141200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM NORTHERN
FLORIDA INTO MUCH OF SOUTH CAROLINA...
...SUMMARY...
A few strong-to-severe storms will be possible from northern Florida
into much of South Carolina.
... Synopsis ...
The persistent CONUS-wide mid-level ridge centered across the
north-central US will begin to flatten and elongate on Monday as a
strong mid-level trough moves across central Canada. As the
mid-level ridge flattens/elongates it will place much of the
southern US in easterly mid-level flow. This easterly mid-level flow
will cause a weak mid-level trough across the Tennessee Valley to
retrograde. This high-over-low pattern will feature a belt of
enhanced easterlies stretching from the lower Great Lakes west into
the Central Plains.
At the surface, a weak surface low over the southern Appalachians
will redevelop westward toward Alabama during the afternoon. The
combination of this surface low with a surface ridge centered across
the Mid-Mississippi Valley will result in northerly low-level flow
across much of the Ohio and Tennessee Valleys and western parts of
the Southeast.
... Northern Florida into much of South Carolina ...
As the surface low redevelops across Alabama on Monday, this area
will experience southwesterly surface flow that will maintain a
warm, moist airmass. Residual cooler mid-level temperatures (as
compared to surrounding areas) associated with the weak mid-level
trough and strong diurnal heating of this moist airmass will result
in afternoon thunderstorms. Deep-layer shear remains weak across the
area which should limit overall thunderstorm organization, favoring
instead single cells and a few multicell clusters. A few heavy,
water-loaded downdrafts will be capable of producing sporadic wind
damage.
..Marsh.. 07/11/2026
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SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0200 AM CDT Sat Jul 11 2026
Valid 111200Z - 121200Z
...Synopsis...
An upper-level low deepening and progressing eastward towards
coastal British Columbia will serve to intensify the height gradient
with an upper-level ridge centered over the Great Basin. The
intensification of the mid-level jet streak across the northern
Sierra Nevadas and Cascades will have a modest cross-range
component, and deep boundary-layer mixing beneath this jet should
result in dry and windy conditions supporting at least an Elevated
fire-weather threat.
The best combination of winds and relative humidity is forecast to
be from portions of northeastern California into southern Oregon,
where winds should reach 15-20 MPH with 10-15% relative humidity.
With fuels guidance showing ERCs around the 80th annual percentile,
at least Elevated fire-weather concerns are expected. There may be
some locally Critical conditions where favored by local topography,
but the expectation is that these will be spatially limited and
shorter duration.
Elevated highlights extend northward into the Washington Cascades,
and eastward into portions of Idaho and Montana, but the wind
magnitudes are forecast to be 10-15 MPH with 15-20% relative
humidity. While the meteorological conditions are not quite as
favorable, fuels guidance suggests more than sufficient
receptiveness to wildfire ignition and spread given ERCs in the
90th-95th annual percentiles.
..Halbert.. 07/11/2026
...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
0205 AM CDT Sat Jul 11 2026
Valid 121200Z - 131200Z
...Synopsis...
An upper-level trough and associated jet streak is forecast to
progress east-northeastward from British Columbia into the interior
Canadian provinces on Sunday as an upper-level ridge moves from the
Great Basin into the High Plains. Residual flow across the Pacific
Northwest from the ejecting trough and a deepening surface low
across eastern Montana will be responsible for at least Elevated
fire-weather concerns across the Intermountain West to the northern
High Plains.
...Eastern Idaho into southern Montana, Eastern Wyoming, and far
western portions of the Dakotas...
A deepening surface cyclone will be responsible for bringing gusty
conditions to portions of the northern High Plains into Idaho, where
winds are forecast to be around 20 MPH, potentially gusting to 25-30
MPH. Widespread relative humidity at or even below 10% with these
forecast wind gusts will support Elevated to potentially Critical
fire-weather conditions on Sunday. However, there is currently some
uncertainty in the receptiveness of fuels across the region. ERCs
fuels guidance exceeds the 90th-95th annual percentiles, but other
sources suggest there may be more green vegetation that is not
accounted for in ERCs. Given the uncertainty in the quality of
fuels, only Elevated highlights have been maintained. However,
further upgrade to Critical in the Day 2 update is possible as
forecast guidance and fuel readiness become clearer.
...Northeastern California/northwestern Nevada into southern
Oregon...
Dry and breezy conditions associated with the ejecting mid-level jet
will linger across portions of the northern Sierra Nevadas into the
Cascades on Sunday. Winds of 10-15 MPH and relative humidity of
10-15%, combined with modestly receptive fuels (ERCs at the 80th
annual percentile) will support Elevated fire-weather conditions.
..Halbert.. 07/11/2026
...Please see www.spc.noaa.gov/fire for graphic product...
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