956
ACUS01 KWNS 140548
SWODY1
SPC AC 140546

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1246 AM CDT Mon Jul 14 2025

Valid 141200Z - 151200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN PARTS OF THE
NORTHERN...EASTERN...AND SOUTHWEST STATES...

...SUMMARY...
Isolated severe thunderstorms are possible across the northern
High/Great Plains, East, Mid-South, and southeast Arizona this
afternoon into tonight.

...Northern High/Great Plains...
A shortwave trough will dig south across BC and reach the northern
Rockies by 12Z Tuesday. A belt of strong mid-level westerlies will
be centered along the international border through the Upper
Midwest, with downstream low-amplitude shortwave impulses across
south-central Canada. This setup will yield a pronounced
west/east-oriented surface front, with the gradient strengthened by
differential heating, bisecting MT to northern MN. The western
portion of the front will steadily progress south as a cyclone
develops near the MT/ND/SD border.

Scattered to numerous late-afternoon/early evening thunderstorms are
likely over the higher terrain in an arc from the MT/WY border
across western SD and the WY/NE border area. This initial activity
will be high-based with deep inverted-v thermodynamic profiles
downstream, supporting sporadic severe gusts amid weaker deep-layer
shear with southern extent. A couple short-lived supercells may
develop within a mesoscale corridor downstream into the
south-central ND vicinity. Pronounced MLCIN in the warm/moist sector
with southeast extent should mitigate greater severe coverage.
Otherwise, mainly elevated thunderstorms will become prevalent from
dusk through the overnight across north-central MT to northern MN.
Given the aforementioned strong mid-level westerlies, isolated
severe hail and locally strong gusts will be possible into early
morning Tuesday.

...East...
Within a persistent high PW air mass from the Northeast to FL,
greater boundary-layer heating is expected from MD southward. This
will yield a broad swath of 2000-3000 J/kg MLCAPE by afternoon.
Farther north, more limited heating is anticipated, muting buoyancy
amid weak mid-level lapse rates. Scattered to numerous thunderstorms
will develop from southeast NY to FL. Deep-layer shear will be weak,
but could be slightly greater in the Northeast ahead of an MCV
(currently over OH) and in FL amid modest mid-level northerlies.
Similar to recent days, isolated damaging winds are anticipated.

...Mid-South...
An MCV near FSM should drift east-northeast with an accompanying
belt of modestly enhanced 700-mb southwesterlies to its immediate
southeast. This may support an isolated damaging wind threat by
afternoon, along the northern periphery of ample buoyancy over the
Lower MS Valley to Deep South.

...Southeast AZ...
With a mid-level anticyclone remaining anchored over the southern
Great Basin, modestly enhanced northeasterlies will envelop most of
southern AZ by peak heating. Guidance signals are mixed on whether a
slow-moving cluster may develop off the higher terrain of the AZ/NM
border region. Consensus suggests more discrete activity. But
similar to Sunday evening, a short-lived cluster may form with a
primary threat of localized severe gusts.

..Grams/Thornton.. 07/14/2025

$$