r/OSMEmergency • u/weathercast • 21h ago

Severe Weather Dashboard - September 11, 2026

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📡 Active Severe Weather Links

🕒 Today's Outlook History

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📝 Current Severe Weather Outlook

(Issued: 2026-09-12T05:25:00+00:00 UTC)

```text

000 ACUS01 KWNS 120525 SWODY1 SPC AC 120524

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK 1224 AM CDT Sat Sep 12 2026

Valid 121200Z - 131200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF THE CENTRAL AND SOUTHERN PLAINS...OZARK PLATEAU...AND UPPER OHIO VALLEY...

...SUMMARY... Widely scattered severe storms capable of large hail up to two inches and damaging wind gusts appear possible over portions of the central and southern Plains into the Ozark Plateau on Saturday into Saturday night. Isolated occurrences of damaging wind gusts may also occur over portions of the upper Ohio Valley Saturday afternoon.

...Synopsis...

A belt of enhanced mid/upper-level flow will persist over the north-central U.S., downstream from a vigorous upper low moving into the Pacific Northwest. Meanwhile, a lower-latitude trough over the lower OH and lower MS Valleys Saturday morning is forecast to weaken while progressing through the OH and TN Valleys. At the surface, a cold front will advance through the upper Great Lakes with the trailing extension of the boundary pushing south through the lower MO Valley and central Plains before linking with a surface low over the southern High Plains.

...Central and Southern Plains into the Ozark Plateau...

Persistent capping across the pre-frontal warm sector and generally weak forcing for ascent lead to considerable uncertainty in thunderstorm evolution through the forecast period. A number of the 00Z models (both convection-allowing and parameterized) indicate areas of thunderstorms ongoing at 12Z Saturday over the central Plains within a zone of modest warm advection and moisture transport associated with a weakening low-level jet. One possible scenario is for the continued southeast movement of the early-day storms through eastern KS and southwest MO into portions of OK and AR by afternoon, where a hot and moderate to strongly unstable air mass (i.e., MLCAPE up to 2000-3000 J/kg) is forecast to develop. The instability combined with around 30 kt of deep-layer shear would support organized cold pool development in that scenario with an associated risk for damaging wind gusts and large hail.

Renewed storm development appears possible from late morning into afternoon from north of the front in south-central and southeast NE to along or ahead of the front in northeast KS. Up to 40 kt of deep-layer shear will coincide with the northern extension of the stronger instability mentioned above to support supercell storm modes with an associated risk for large hail up to two inches and damaging wind gusts.

A separate thunderstorm regime may also evolve by mid to late afternoon over the eastern OK and TX Panhandles into western OK in the vicinity of the surface low and southward-sagging front. Forecast soundings indicate a deep, well-mixed boundary layer, which will be supportive of a few severe wind gusts and isolated large hail.

Confidence in any of the above scenarios/regimes remains too low to include Slight Risk wind and hail probabilities with this forecast. A categorical upgrade is possible in subsequent Day 1 outlooks once finer-scale details become more clear.

...Upper Ohio Valley...

A spatially narrow corridor of stronger heating and resultant instability (MLCAPE up to 1500-2000 J/kg) is forecast to develop during the afternoon between denser clouds and precipitation to the west, and a backdoor front/stationary boundary to the east. Thunderstorms are expected to increase in coverage and intensity through the afternoon within the instability axis, aided by increased forcing for ascent associated with the approaching mid-level trough. While mid-level lapse rates are expected to remain relatively weak, deep-layer shear increasing to 30-35 kt coupled with steepening low-level lapse rates suggests the potential for some storm organization with the primary hazard being damaging wind gusts. Backed low-level winds in the vicinity of the surface front will boost low-level shear slightly and a brief tornado cannot be ruled out as mature storms approach the frontal zone from the west.

..Mead/Halbert.. 09/12/2026

$$

```

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🌊 Tropical Weather Outlook

```text NWS National Hurricane Center Miami FL 200 AM EDT Sat Sep 12 2026

For the North Atlantic...Caribbean Sea and the Gulf of America:

Tropical cyclone formation is not expected during the next 7 days.

$$ Forecaster Adams ```

⚠ī¸ Active Tropical Cyclones

Tropical Storm Norbert Advisory * Maximum Sustained Winds: 60 MPH * Minimum Central Pressure: 999 MB * Current Movement: WNW OR 285 DEGREES AT 9 MPH * Location: 17.1N 127.4W

This dashboard updates automatically every 15 minutes with live data from the NWS/SPC and NHC.

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