Day 1 Convective Outlook RESENT 1
NWS Storm Prediction Center Norman OK
0933 PM CDT Wed Jul 15 2026

Valid 160100Z - 161200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS CENTRAL
TX...SOUTHERN/CENTRAL AZ...SOUTHEAST MT...AND PORTIONS OF CENTRAL OR
INTO SOUTHERN WA...

...SUMMARY...
Isolated damaging winds are possible for portions of the northern
Rockies/High Plains, Pacific Northwest, and Arizona into the early
overnight hours. A brief tornado or two may also occur across parts
of south-central Texas.

...Mid-Atlantic/Northeast...

Severe probabilities have been removed from the Northeast states
with the 01z update. The 00z OKX RAOB indicated ample inhibition,
which should suppress convection the remainder of the evening.
Despite strong deep-layer northwesterly flow and modest midlevel
lapse rates supporting elevated instability, it is unlikely
additional convection will develop overnight as a midlevel shortwave
impulse increasingly moves offshore over the Atlantic.

Some guidance suggests that convection ongoing over southern Lower
MI may continue to develop/percolate southeast overnight across Lake
Erie and into northeast OH/northwest PA within strong northwesterly
mid/upper flow. The 00z PIT RAOB shows steep lapse rates and large
instability. However, inhibition should increase with loss of
daytime heating. An isolated strong storm producing small hail
cannot be ruled out, but overall severe potential appears limited
given time of day and nebulous forcing for ascent.

...Central Texas...

Rounds of thunderstorms will continue overnight as lobes of
convectively enhanced vorticity maxima rotate around the mid/upper
low centered over west-central TX. Low-level warm advection will
persist through the night, maintaining rich boundary layer moisture,
maintaining at least modest low-level instability. Vertically
veering low-level wind profiles will maintain 0-1 km SRH around
100-200 m2/s2, and a tornado or two will remain possible.

...AZ...

Strong thunderstorms could produce locally damaging/severe gusty
outflow winds through late evening. Reference MCD 1628 for
information on short term severe potential.

...MT/WY...

Severe probabilities have mostly be removed from WY and confined to
MT, where modest instability overlaps with strong effective shear
magnitudes. Isolated strong wind gusts remain possible through late
evening as convection shifts east toward a better low-level lapse
rate environment.

...WA/OR...

Scattered high-based showers and thunderstorms will persist tonight
across central OR into south-central WA. A belt of 30-40 kt
effective shear magnitudes may provide sufficient support within the
weakly unstable airmass for a couple of strong storms. Steep lapse
rates will favor strong outflow winds with this convection.

..Leitman.. 07/16/2026

Day 1 Convective Outlook  
NWS Storm Prediction Center Norman OK
1218 AM CDT Thu Jul 16 2026

Valid 161200Z - 171200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
WESTERN MONTANA...

...SUMMARY...
Severe thunderstorms will be possible across parts of western
Montana, mainly Thursday afternoon and evening. Locally damaging
winds may also occur across parts of New England, the Upper Midwest,
and the Mid-Atlantic.

...Northern Rockies...

An upper low will skim the Pacific Northwest coast as it lifts
northward through the period. Meanwhile, upper ridging will persist
across much of the Rockies to the Plains. Wedged between the upper
low and the western periphery of the upper ridging, a belt of
enhanced south/southwesterly deep-layer flow will overspread the
northern Rockies. Easterly low-level flow will transport 50s F
dewpoints across region beneath steep midlevel lapse rates. This
will support moderate destabilization (1000-2000 J/kg MLCAPE).
Scattered thunderstorms will develop during the afternoon.
Vertically veering wind profiles and increasing flow aloft will
result in 30+ kt effective shear magnitudes. Organized cells will
pose a risk for strong wind gusts and hail across much of the
region. The greatest risk for 1+ inch hail will be across portions
of western MT.

...New England...

A vigorous upper shortwave trough will move across the region
through evening. Strong west/northwest deep-layer flow is evident in
forecast soundings, with 40+ kt effective shear magnitudes likely.
Boundary layer moisture will be somewhat muted compared to the
previous few days, with dewpoints generally in the 50s F. Stronger
heating is expected to the north of the more prominent smoke plume
across southern New England, aiding in steepening low-level lapse
rates. While instability will remain modest, strong flow and steep
low-level lapse rates may support isolated strong/locally damaging
wind gusts as convection spreads southeast from Quebec and across
portions of northern New England through the afternoon.

...Southern PA/Mid-Atlantic vicinity...

Strong mid/upper-level flow will overspread the region on the
southern periphery of the upper shortwave trough moving across New
England. A surface front is expected to drop southward through the
day, approaching the PA/MD border vicinity by late afternoon. Rich
boundary layer moisture will be in place ahead of the surface front
and beneath steep midlevel lapse rates. This will foster a corridor
of 2000+ J/kg MLCAPE. Furthermore, forecast soundings show 30-40 kt
effective shear magnitudes and steep low-level lapse rates. This
environment generally should support organized cells/line segments.
However, convective coverage is uncertain given stronger forcing for
ascent focused north of the area. Additionally, it is uncertain if
smoke will continue to have a deleterious impact on an otherwise
favorable severe storm environment. Given conditional potential for
at least locally damaging gusts, have included low severe wind
probabilities.

...ND/MN...

A series of convectively enhanced vorticity maxima will migrate
across the Canadian Prairies atop the upper ridge and through
northwesterly flow aloft into parts of ND and northern MN this
afternoon into tonight. At the surface, a weak low and surface front
will move across ND into northern MN during the evening and
overnight hours. South/southeasterly low-level flow will maintain a
moisture-rich boundary layer, supporting a corridor of modest
destabilization. Forecast soundings show supercell wind profiles,
but also increasing capping through the late afternoon/evening.
Nevertheless, most guidance develops convection across southern
Manitoba into northeast ND during the evening, spreading
east/southeast across northern MN during the nighttime hours. Some
risk for strong gusts and marginal hail appears possible,
necessitating low severe probabilities. 

...AZ...

Thunderstorms are expected once again to develop over higher terrain
this afternoon/evening and spread westward across portions of
central/southern AZ. Deep layer flow will be weaker compared to
previous days, but modest instability and steep lapse rates amid
strong heating could support sporadic strong gusts.

..Leitman/Lyons.. 07/16/2026

Day 2 Convective Outlook  
NWS Storm Prediction Center Norman OK
0105 AM CDT Thu Jul 16 2026

Valid 171200Z - 181200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
OF NORTHERN IDAHO AND WESTERN MONTANA AS WELL AS PORTIONS OF THE
UPPER MIDWEST AND NORTHERN GREAT LAKES...

...SUMMARY...
Strong to potentially severe storms are possible on Friday across
parts of western Montana and northern Idaho, and also across parts
of the Upper Great Lakes region.

... Parts of the Upper Midwest and Great Lakes ...

A subtle mid-level vorticity maximum evident in the 16/00 UTC
guidance is expected to move southeastward across northern Minnesota
and the Upper Great Lakes on Friday morning, supporting ongoing
thunderstorms across the Arrowhead of Minnesota. This activity
should spread southeastward through the morning with at least a
marginal severe hail/wind threat. 

During the day, a surface frontal zone draped from northern
Illinois/Indiana should begin to lift northward, ahead of a surface
cold front moving through the northern Plains. To the south of the
warm front and ahead of the cold front, diurnal heating may be
somewhat muted by smoke and residual cloud cover from morning
convection. However, increasing low-level moisture should still
support moderate destabilization by the afternoon, especially where
stronger diurnal heating occurs. Moderate mid-level northwesterly
flow will provide enough vertical shear to support organized storms.

As the stronger mid-level wave approaches the region during the late
afternoon and evening, some potential exists for surface-based
thunderstorm redevelopment -- especially near the intersection of
the cold front and effective warm front. Large hail and strong
thunderstorm winds will be possible with these storms, and the
low-level wind field would support at least some potential for a
tornado with any sustained surface-based storm during the evening.
With time this activity should evolve into one or more clusters of
thunderstorms moving southeast overnight across the northern Great
Lakes. 


... Western Montana and Northern Idaho ...

A relatively favorable thermodynamic environment will once again be
in place across parts of western Montana and northern Idaho by
Friday afternoon. Relatively steep low- and mid-level lapse rates,
sufficient moisture, and diurnal heating should support afternoon
SBCAPE values in the 1000-1500 J/kg range, as suggested by the
20260716 00UTC HREF. Mid-/upper-level flow will be less than in
previous days as the region becomes increasingly displaced from a
mid-/upper-level trough/low moving northward into southwest Canada.
That said, effective-layer shear on the order of 25-35 knots will be
possible, especially where east/southeasterly surface winds are
maintained. 

Scattered thunderstorms are expected to develop during the afternoon
and evening hours. The strongest thunderstorm clusters will be
capable of large hail. Strong to severe thunderstorm gusts will be
possible as well, especially where convective outflows can
consolidate amid the steep low-/mid-level lapse rates. Most 16/00
UTC HREF members show explicit convective outflow gusts approaching
60 mph, supporting a localized severe threat.

If convective coverage appears greater than currently forecast,
severe probabilities may need to be increased in subsequent
outlooks.


... Ohio Valley ...

Scattered to numerous thunderstorms are expected to develop during
the afternoon within a moist, moderately unstable, and weakly capped
environment. Localized downburst winds could occur within this
environment, though deep-layer flow/shear appears too weak to
support an organized severe threat. Additionally, 16/00 UTC guidance
suggests early initiation across the region, which would limit the
development of widespread steep low-level lapse rates, which may
provide some limit on a more widespread, storm-scale driven wind
threat. This region will continue to be evaluated in subsequent
outlooks.

..Marsh.. 07/16/2026