


Severe Storm Outlook Narrative (AC)
Issued by NWS
Issued by NWS
Versions:
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
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 $$