SPC Jul 13, 2026 1300 UTC Day 1 Convective Outlook

LIVE MAP (ABOVE) ... SPC 1300Z Day 1 Outlook


Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0730 AM CDT Mon Jul 13 2026

Valid 131300Z - 141200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE SOUTHEAST AND MONTANA...

...SUMMARY...
Thunderstorms with isolated strong to severe winds may occur this
afternoon and evening across parts of the Southeast and Montana.

...Southeast...
A very weak mid-level trough will persist over the Deep South and
Carolinas today, with modest westerly flow. Although rich low-level
moisture remains present across these areas, multiple days of
convective overturning has resulted in rather poor lapse rates
aloft. This, along with persistent cloudiness, should limit to some
degree how much instability will develop this afternoon with
filtered daytime heating. Deep-layer shear will also remain weak,
and thunderstorms should generally be disorganized. Some loose
clustering may eventually occur with convection spreading eastward
from the central Gulf Coast towards the FL Peninsula, where
low-level lapse rates should become steepened by peak afternoon
heating. Isolated damaging winds appear possible with the strongest
cores from parts of FL into eastern GA and SC ahead of the weak
mid-level trough.

...Montana...
Mid/upper-level ridging will extend from the southern/central
Rockies to the northern Plains/Upper Midwest through the period,
with a belt of enhanced southwesterly mid-level flow over
western/central MT. High-based thunderstorms may develop this
afternoon across parts of southwest into central MT amid a deeply
mixed boundary layer. While low-level moisture and related
instability are both expected to remain limited, some risk for
occasional strong to severe gusts may accompany this convection as
it spreads northward through the early evening before weakening.

...Arizona...
Showers and isolated thunderstorms are still ongoing this morning
across parts of southern AZ. While mid-level east-southeasterly flow
will persist today across much of AZ on the southern periphery of
prominent upper ridging, it remains unclear how much destabilization
will occur in the wake of this morning's convection. Whether
convection will be able to spread westward off the higher terrain of
southeast AZ and the Mogollon Rim is also uncertain. Have therefore
not included low severe wind probabilities with this update.

..Gleason/Thornton.. 07/13/2026


Read more CHECK UPDATE ZOOM GRAPHIC


http://dlvr.it/TTWFVj

SPC Jul 13, 2026 0600 UTC Day 1 Convective Outlook

LIVE MAP (ABOVE) ... SPC 1200Z Day 1 Outlook


Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1253 AM CDT Mon Jul 13 2026

Valid 131200Z - 141200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE SOUTHERN ATLANTIC SEABOARD AND IN WESTERN MONTANA...

...SUMMARY...
Thunderstorms with isolated severe wind gusts will be possible from
mid afternoon into early this evening across parts of the southern
Atlantic Seaboard and in western Montana.

...Southern Atlantic Seaboard...
Very moist air will be in place today from the Southeast eastward to
the southern Atlantic Seaboard. Surface dewpoints across Georgia and
South Carolina will be mostly in the 70s F. As surface temperatures
warm today, moderate instability will develop across much of the
region. Scattered thunderstorms will form in the higher terrain of
the southern Appalachians and within zones of low-level convergence
across the moist airmass. As instability maximizes and low-level
lapse rates steepen this afternoon, a few severe wind gusts will be
possible with the stronger cells.

...Western Montana...
Southwesterly mid-level flow will be in place today across the
northwestern U.S. At the surface, upslope flow will be located from
the northern High Plains westward to the northern Rockies. As
surface temperatures warm today, a pocket of instability will
develop across western Montana adjacent to the higher terrain. Some
storms that form in the northern Rockies will move northeastward
toward and through this pocket of instability in the lower
elevations, where SBCAPE could approach 1000 J/kg late this
afternoon. The instability and very steep low to mid-level lapse
rates will contribute to a potential for isolated severe wind gusts.

..Broyles/Halbert.. 07/13/2026


Read more CHECK UPDATE ZOOM GRAPHIC


http://dlvr.it/TTVrZg

SPC Jul 13, 2026 0100 UTC Day 1 Convective Outlook

LIVE MAP (ABOVE) ... SPC 0100Z Day 1 Outlook


Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0801 PM CDT Sun Jul 12 2026

Valid 130100Z - 131200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE SOUTHERN ATLANTIC SEABOARD...AND IN SOUTHERN ARIZONA...

...SUMMARY...
Thunderstorms with severe wind gusts will be possible this evening
across parts of the southern Atlantic Seaboard and in southern
Arizona. Severe gusts and hail may also occur in parts of the
western Great Lakes. A few strong gusts will also be possible in
northeast Montana, and from the southern Plains into the Southeast.

...Southern North Carolina/South Carolina/Far Eastern Georgia...
A mid-level shortwave trough is evident on water vapor imagery from
the Mid-Atlantic into the Carolinas. At the surface, a cold front is
located over southern North Carolina. To the south of the front, a
very moist air is in place with dewpoints in the 70s F, which is
contributing to moderate instability. Scattered thunderstorms are
ongoing across much of this airmass from southern North Carolina
into eastern Georgia. The latest WSR-88D VWPs at Wilmington, North
Carolina and Colubmia, South Carolina have 0-6 km shear in the 20 to
30 knot range. This environment may support a threat for severe wind
gusts for another hour early this evening.

...Southern Plains/Lower Mississippi Valley/Southeast...
A very moist airmass is in place from the southern Plains eastward
into the Southeast. Over much of the region, the RAP has moderate
instability, with surface dewpoints in the 70s F. Numerous
thunderstorms are ongoing from north-central Texas eastward into
southern Alabama. Along this corridor, the instability combined with
steep low-level lapse rates will support a threat for isolated
severe gusts for another hour or two.

...Southern Arizona...
At the surface, a sufficiently moist airmass is in place over
southern and central Arizona. In this area, the RAP has an axis of
moderate instability analyzed with SBCAPE estimated in the 1000 to
2000 J/kg range. Thunderstorms are ongoing just to the west of the
instability axis, and these storms will continue to move westward
across southern and western Arizona this evening. Large surface
temperature-dewpoint spreads and steep low-level lapse rate will
continue to support a potential for severe wind gusts...see MCD
1609.

...Western Great Lakes...
North-northwesterly mid-level flow is located over the western Great
Lakes, where a moist airmass is present. Surface dewpoints are in
the 60s and lower 70s F, and the RAP has an axis of moderate
instability from northern Wisconsin into Upper Michigan. Scattered
strong to severe storms are ongoing further north over southern
Ontario. One of these cells could remain intact and move southward
across Lake Superior into Upper Michigan this evening. In that case,
the instability combined with moderate deep-layer shear would
support an isolated threat for severe wind gusts and hail.

...Northern Montana...
Southwest mid-level flow is in place over the northwestern U.S. At
the surface, a cold front is located over central and northeast
Montana, where isolated thunderstorms are ongoing. Near and ahead of
the front in northeast Montana, the RAP is analyzing moderate
instability. Thunderstorms that move in and toward the stronger
instability over the next couple of hours, may produce isolated
severe wind gusts...see MCD 1610.

..Broyles.. 07/13/2026


Read more CHECK UPDATE ZOOM GRAPHIC


http://dlvr.it/TTVXxy

SPC Jul 12, 2026 1630 UTC Day 1 Convective Outlook

LIVE MAP (ABOVE) ... 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


Read more CHECK UPDATE ZOOM GRAPHIC


http://dlvr.it/TTVP28