RSS Mesoscale Discussions from Storm Prediction Center
No watches are valid as of Sun Jul 12 17:27:02 UTC 2026.
MD 1601 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR PORTIONS OF EASTERN GEORGIA INTO MUCH OF SOUTH CAROLINA
Mesoscale Discussion 1601
NWS Storm Prediction Center Norman OK
1224 PM CDT Sun Jul 12 2026
Areas affected...portions of eastern Georgia into much of South
Carolina
Concerning...Severe potential...Watch possible
Valid 121724Z - 121930Z
Probability of Watch Issuance...40 percent
SUMMARY...Thunderstorm coverage will increase over the next 1-2
hours across portions of Georgia and South Carolina, bringing a
threat for damaging wind gusts. A Severe Thunderstorm Watch may
eventually be needed.
DISCUSSION...A hot, humid air mass remains in place across much of
the Southeast, with temperatures noted to have already warmed into
the low/mid 90s across portions of eastern Georgia and
southern/central South Carolina as of 1720 UTC. Visible satellite
imagery depicts increasingly agitated cumulus across the region,
with developing thunderstorms noted south and east of the Atlanta
Metro. Continued heating of this air mass will promote further
destabilization through the afternoon to around 2000-3000 J/kg
MLCAPE and increasing convective coverage over the next couple of
hours. Weak deep-layer flow and effective shear suggest a relatively
disorganized, outflow-dominant storm mode, but steepening low-level
lapse rates and PW content near 2 inches will facilitate a risk for
damaging wind gusts (with gusts up to around 60 mph possible) across
the region. A Severe Thunderstorm Watch may be needed to cover this
potential within the next 1-2 hours.
..Chalmers/Smith.. 07/12/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...ILM...CHS...CAE...GSP...JAX...FFC...TAE...
LAT...LON 31108148 31208198 31558281 32228339 33018366 33218367
33718370 34098354 34338330 34488288 34648187 34578083
34308014 33917962 33567927 33227913 33087918 32577979
32128051 31768094 31188117 31108148
MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH
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MD 1600 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR NORTHEAST TX VICINITY INTO NORTHERN LA
Mesoscale Discussion 1600
NWS Storm Prediction Center Norman OK
1212 PM CDT Sun Jul 12 2026
Areas affected...northeast TX vicinity into northern LA
Concerning...Severe potential...Watch unlikely
Valid 121712Z - 121915Z
Probability of Watch Issuance...20 percent
SUMMARY...Scattered to numerous thunderstorms are expected through
the afternoon. Sporadic strong gusts are possible, though severe
potential is expected to remain limited.
DISCUSSION...A very moist airmass characterized by 70s F dewpoints
is in place across the ArkLaTex vicinity this afternoon. Strong
heating of this very moist airmass along a west to east oriented
surface boundary is supporting moderate instability as of midday.
Thunderstorms are already developing along this boundary, and on the
southern periphery of a convectively enhanced vorticity maxima.
Vertical shear will remain weak today, limiting a more organized
severe risk. However, steepening low-level lapse rates through the
afternoon in conjunction with water laden downdrafts, could support
sporadic wet microbursts, with a few stronger gusts possible. A
severe thunderstorm watch appears unlikely at this time.
..Leitman/Smith.. 07/12/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...JAN...SHV...TSA...HGX...FWD...OUN...
LAT...LON 34149707 33849510 33149259 32639155 32239147 31769188
31489324 31489507 31929657 32309732 32919764 33569765
33869761 34149707
MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH
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MD 1599 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PORTIONS OF NORTH FLORIDA AND THE FLORIDA PANHANDLE INTO SOUTHWESTERN GEORGIA AND SOUTHEASTERN ALABAMA
Mesoscale Discussion 1599
NWS Storm Prediction Center Norman OK
1200 PM CDT Sun Jul 12 2026
Areas affected...portions of North Florida and the Florida Panhandle
into southwestern Georgia and southeastern Alabama
Concerning...Severe potential...Watch unlikely
Valid 121700Z - 121900Z
Probability of Watch Issuance...20 percent
SUMMARY...Isolated damaging wind gusts and perhaps an instance or
two of small hail will be possible over the next several hours.
DISCUSSION...Scattered thunderstorms have developed along the Gulf
Coast sea breeze from the Florida Panhandle into North Florida amid
a hot and humid air mass, with a couple of gusts measured in the
40-45 mph range over the past 1-2 hours. Temperatures near 90 F and
dewpoints in the low/mid 70s are already supporting 2000-3000 J/kg
MLCAPE, with further destabilization expected through peak heating
this afternoon. Coupled with high PW (greater than 2 inches) and
steepening low-level lapse rates, an isolated risk for water-loaded
downbursts, damaging wind gusts (with localized gusts to 65 mph
possible), and perhaps an instance or two of small hail should
materialize across the region. Weak effective shear and deep
layer-flow will temper overall convective intensity and
organization. Thus, watch issuance appears unlikely at this time.
..Chalmers/Smith.. 07/12/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...MLB...TBW...JAX...TAE...BMX...MOB...
LAT...LON 30528654 30638694 30848714 31148709 31568668 31778581
31678470 31288317 30858213 30528168 30228136 29838111
29518091 29118076 28828072 28528094 28338128 28228167
28228197 28298217 28428230 28698254 28918284 29198312
29588346 29968402 29998425 29878444 29718466 29558488
29548531 29708548 29968570 30208601 30528654
MOST PROBABLE PEAK WIND GUST...55-70 MPH
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SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0732 AM CDT Sun Jul 12 2026
Valid 121300Z - 131200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
EASTERN GEORGIA INTO THE CAROLINAS...SOUTHERN/CENTRAL ARIZONA...AND
THE UPPER PENINSULA OF MICHIGAN...
...SUMMARY...
Thunderstorms capable of producing isolated to scattered
severe/damaging winds may occur this afternoon/evening across parts
of the Carolinas/Southeast into the southern Plains, and separately
over southern/central Arizona. Large hail and severe winds also
appear possible over portions of the Upper Peninsula of Michigan.
...Carolinas/Southeast into the Southern Plains...
Multiple rounds of thunderstorms over the past couple of days have
convectively overturned the moist airmass across the Carolinas.
Cloud cover is also a bit more prevalent this morning across this
region per recent visible satellite imagery, with a weak surface
front extending generally east-west across NC. This cloudiness may
tend to delay/hinder daytime heating and related steepening of
low-level lapse rates to some extent. But, filtered heating through
cloud breaks and the presence of low to mid 70s surface dewpoints
should still aid in at least weak to moderate instability developing
south of the front by mid afternoon. Current expectations are for
scattered thunderstorms to once again develop this afternoon over
the higher terrain of the Appalachians and vicinity as a weak
mid-level trough/shear zone spreads slowly eastward from the TN
Valley to the Carolinas by this evening. While deep-layer shear will
remain modest, this convection should spread generally eastward,
with some potential for loosely organized clusters capable of
producing isolated to scattered damaging winds. Severe wind
probabilities have been generally adjusted southward based on latest
observational and guidance trends. Thunderstorms developing this
afternoon along/near the Atlantic Coast sea breeze across the FL
Peninsula may also pose an isolated severe/damaging wind threat.
Farther west into the lower MS Valley and southern Plains,
deep-layer flow/shear is expected to remain rather weak. While
thunderstorms will occur along/south of a convectively reinforced
boundary, they should generally remain quite limited in
organization. Still, a risk for locally severe/damaging winds may
exist this afternoon as temperatures warm and the moist low-level
airmass south of the boundary destabilizes with daytime heating.
...Upper Midwest/Great Lakes...
Upper ridging is expected to build northward through the period
across the northern Plains/Upper Midwest, with an EML and associated
steep mid-level lapse rates advecting eastward across the upper
Great Lakes. Diurnal heating of a moist low-level airmass and the
presence of the EML will support moderate to locally strong
instability across this region by early afternoon. Modest
west-southwesterly low-level flow will veer strongly with height
through mid/upper levels to north-northwesterly, aiding 30-40+ kt of
deep-layer shear.
The potential for southward-moving supercells capable of producing
both large hail and severe/damaging winds remains apparent,
especially across the U.P of MI with multiple supercells already
ongoing across northern Lake Superior/Isle Royale this morning.
There is still some uncertainty whether these supercells can be
sustained with southward extent, as temperatures are forecast to
gradually warm through the day in the 850-700 mb layer in tandem
with the EML. Regardless, the ongoing severe thunderstorms this
morning, coupled with potential for additional robust convection
spreading southeastward from western Ontario later today, justify
greater severe hail/wind probabilities across parts of the U.P of
MI. Isolated 2+ inch diameter hail appears possible given the strong
deep-layer shear, steepening mid-level lapse rates, and expected
supercell mode.
...Arizona...
Mid/upper-level ridging will remain prominent today over the Rockies
and Plains, with around 20-30 kt of easterly mid-level flow
persisting over AZ/NM. Ongoing showers and thunderstorms this
morning will shift westward through the day, with ample daytime
heating still anticipated for much of southern/central AZ. The
boundary layer will become very well mixed by mid afternoon as
surface temperatures reach into the 90s/low 100s. Orographic lift
should aid parcels in reaching their LFCs over the higher terrain
along the Mogollon Rim and in southeast AZ. The modestly enhanced
easterly mid-level flow should aid this activity in spreading
generally westward into the lower elevations of southern/central AZ
through the remainder of the afternoon and continuing into the
evening. Scattered severe/damaging winds will likely be the main
threat given steepened low-level lapse rates and efficient momentum
transfer in convective downdrafts. Some potential for clustering may
exist, and the severe wind probabilities have been expanded westward
across more of southern/central AZ with this update.
...Montana...
The potential for locally strong/gusty winds may exist this
afternoon with high-based convection that could spread from
southwest into northern MT on the northwestern periphery of the
amplified upper ridge over the Rockies/Plains. Confidence in
sustained thunderstorms developing along/ahead of a weak front
across this region remains rather low due to limited low-level
moisture and capping concerns, so severe wind probabilities have not
been introduced at this time.
..Gleason/Thornton.. 07/12/2026
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SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook CORR 1
NWS Storm Prediction Center Norman OK
1141 AM CDT Sun Jul 12 2026
Valid 121630Z - 131200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
EASTERN GEORGIA INTO THE CAROLINAS...SOUTHERN/CENTRAL ARIZONA...AND
THE UPPER PENINSULA OF MICHIGAN...
CORRECTED FOR OUTLOOK PROBABILITY LINES OVER GA/CAROLINAS
...SUMMARY...
Thunderstorms capable of producing isolated to scattered
severe/damaging winds may occur this afternoon/evening across parts
of the Carolinas/Southeast into the southern Plains, and separately
over southern/central Arizona. Large hail and severe winds also
appear possible over portions of the Upper Peninsula of Michigan.
...Carolinas/Southeast into the Southern Plains...
Midday visible-satellite imagery shows an agitated cumulus field
over north-central GA to the south of a differential heating
zone/weak front draped across the southern Appalachians and west to
east across the Carolinas. Surface temperatures will continue to
warm into the 90s F south of the more prevalent cloud cover over the
Upstate of SC and western/central NC. Scattered thunderstorms will
likely develop in several clusters across the Southeast with strong
to locally severe gusts capable of wind damage being the primary
hazard. Farther west, more widely spaced clusters will likely
develop over the central Gulf Coast states into the Ark-La-Tex
region. Locally damaging gusts will be possible with the stronger
thunderstorms.
Into parts of the southern High Plains, a seasonably moist boundary
layer will become moderately unstable by mid afternoon. Steep 0-3
km lapse rates will favor isolated severe gusts with the stronger
downdrafts. Considered a small Slight Risk over the TX South Plains
but some uncertainty regarding storm coverage precluded higher
severe probabilities this outlook update.
...Upper Midwest/Great Lakes...
Northwest-flow regime will maintain a plume of elevated mixed layer
air atop a moist low-level airmass. It is uncertain whether
additional storm development will occur this afternoon in
association with a morning cluster of strong to severe storms over
parts of the U.P. Nonetheless, sufficient shear/buoyancy for
supercells and organized storms structures lends a continued
conditional risk for severe storms into this evening/tonight. Some
guidance shows an eventual outflow-dominant cluster moving into
parts of the region tonight, with some potential for damaging gusts.
...Arizona...
Very strong heating will again yield a hot and well-mixed boundary
layer by mid afternoon. Isolated to scattered storms are forecast
to develop on the Rim and gradually propagate into the lower desert,
aided by moderate easterly mid-level flow (30-kt at 500 mb sampled
by the 12 UTC Phoenix raob). Strong evaporative cooling of the more
water-laden downdrafts will be capable of severe gusts (60-75 mph).
...Montana...
A weak front along with very strong heating may suffice for a few
high-based thunderstorms to develop late this afternoon across
north-central MT. Very steep low to mid-level lapse rates and deep
inverted-V profiles imply some potential for severe gusts with the
stronger evaporatively cooled downdrafts.
..Smith/Chalmers.. 07/12/2026
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SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1217 PM CDT Sun Jul 12 2026
Valid 131200Z - 141200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS WITHIN PARTS OF
EASTERN GEORGIA INTO SOUTH CAROLINA...AND SOUTHWEST MONTANA...
...SUMMARY...
A few strong-to-severe storms will be possible from South Carolina
into central Georgia and far North Florida on Monday. Additional
isolated severe storms are possible in southwestern Montana.
...Synopsis...
Upper-level ridging will continue to build across the CONUS on
Monday. Strong cyclonic flow will exist across the Pacific Northwest
into the northern Rockies. A weak upper-level low will be present in
the Tennessee Valley/southern Appalachians. A stalled surface
boundary will be draped across the southern Plains into the
Carolinas.
...Georgia/South Carolina...
A stalled surface boundary will continue to be the focus for
convection on Monday. Surface heating is expected to be less than
previous days. Even so, a weak upper low will bring subtle lift/flow
enhancement near the surface boundary. Overall storm organization
will be low. That said, around 20 kt of shear near the boundary,
large PWAT values, and scattered/numerous storms will promote a risk
of water-loaded downdrafts capable of isolated wind damage.
...Southwest Montana...
Model trends have suggested that sufficient moisture/destabilization
will be in place by late afternoon into the evening. Isolated to
widely scattered storms are expected to develop within the higher
terrain and move quickly northeastward. Temperatures in the upper
80s/low 90s F and inverted-v thermodynamic profiles will support a
risk for severe winds.
...Arizona...
Temperatures are expected to be cooler on Monday on account of the
impacts of weekend convection. Coupled with weaker and slightly more
southwesterly mid-level winds, it is not clear how much strong to
potentially severe activity will be able to move off of the Mogollon
Rim during the afternoon/evening. A stronger storm or two could
produce gusty outflow winds where greater heating can occur, but
this activity should be much more spatially limited than previous
days.
..Wendt.. 07/12/2026
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SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1150 AM CDT Sun Jul 12 2026
Valid 121700Z - 131200Z
...CRITICAL FIRE WEATHER AREA FOR SOUTHERN MONTANA INTO PORTIONS OF
IDAHO AND NORTHERN WYOMING...
...Morning Update...
No changes were made to the fire weather risk areas. Very light
showers (with minimal precipitation expected at the surface) are
passing over northeastern CA into south-central OR this morning.
Cloud cover is expected to persist across this region today, which
may alleviate some broader fire concerns; however, afternoon wind
gusts of 25-35 mph amid 80-90th percentile ERCs will maintain
Elevated highlights.
Farther east, mostly clear skies (passing high clouds) and
critically low RH values -- surface observations already depicting
less than 20% RH across eastern ID/southern MT/northern WY -- will
contribute to extensive critical fire weather conditions this
afternoon. A 30-40 kt 700 mb jet will overlap eastern ID and
southern MT, with deeper mixing encouraging strong wind gusts to
reach the surface. South-southwesterly winds of 15-20 mph will
precede an approaching cold front this evening (between 03-06z). A
directional wind shift to northwesterly is expected behind the
front, though initial breezy winds will gradually decline to less
than 10 mph overnight with increasing RH. The cold front is forecast
to stall somewhere across central-eastern MT into far northwestern
ND. Meanwhile, a low-level jet will emerge across eastern MT/WY and
the western Dakotas after 00z (ahead of the cold front), generating
strong southerly wind gusts of 35-45 mph into the overnight hours.
These conditions should be monitored closely as it could further
exacerbate the fire environment, impacting any active wildfires and
control efforts.
See the previous discussion for more information.
..Elizalde-Garcia.. 07/12/2026
.PREV DISCUSSION... /ISSUED 0149 AM CDT Sun Jul 12 2026/
...Synopsis...
An upper-level trough and associated jet streak is forecast to
progress east-northeastward from British Columbia into the interior
Canadian provinces today 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 Elevated to Critical
fire-weather concerns across the Intermountain West to the northern
High Plains.
...Southern Montana into portions of Idaho and northern Wyoming...
As a surface low deepens over eastern Montana this afternoon into
the evening, the intensifying surface pressure gradient will result
in sustained winds of 20-25 MPH across much of the area. Relative
humidity of 10-15% is expected across portions of Idaho into
southwestern Montana, and could get as low as 5-10% in south-central
Montana into northern Wyoming. With ERCs largely in the 80th-95th
annual percentiles across the region, Critical fire-weather
conditions are forecast. As the surface low moves eastward and a
cold front moves through the area, winds will shift from largely
southerly to west-northwesterly but should still be gusting 20-25
MPH.
...Northern High Plains...
Strong southeasterly surface flow ahead of the deepening cyclone
should result in sustained 15-20 MPH winds across the far western
Dakotas into portions of Wyoming and Montana. Relative humidity is
forecast to be in the range of 5-15%, getting more moist with
eastward extent. While ERCs are largely in the 90th-95th annual
percentile range, this guidance does not account for live fuels and
the current state of green vegetation. Given the uncertainty in the
quality of fuels with this eastward extent, Elevated fire-weather
highlights have been maintained -- though periods of Critical
meteorological conditions will be possible.
...Southern Oregon into portions of northern Nevada and
California...
Lingering dry and breezy conditions in the wake of the ejecting
mid-level jet streak will persist this afternoon across portions of
northeastern California/northwestern Nevada into southern Oregon.
Winds of 15-20 MPH and relative humidity around 15-20% will overlap
with modestly receptive fuels, resulting in Elevated fire-weather
concerns.
...Southern and Central California...
Isolated to scattered high-based showers appear possible across
portions of California. Occasional lightning is possible, but
limited buoyancy puts the likelihood at less than 10% coverage.
Portions of the Mojave and Sonoran Deserts may see a mix of wet and
dry thunderstorm activity, but uncertainty in the coverage and
rainfall amounts precludes highlights at this time.
...Please see www.spc.noaa.gov/fire for graphic product...
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