Day 1 Severe Weather Outlook

USA Weather — Severe Weather Division

This outlook is expired and is no longer valid.

Issued
16:26Z Sat, Sep 10
Valid
12Z Sat, Sep 10 - 12Z Sun, Sep 11
Forecaster
Wyatt Huber

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE SOUTHEAST INTO THE CAROLINAS...INCLUDING MUCH OF FLORIDA...

...SUMMARY...

ISOLATED WEAK TORNADOES AND A FEW DAMAGING WIND GUSTS WILL BE THE MAIN THREATS FROM THUNDERSTORMS TODAY. SMALL HAIL IS ALSO POSSIBLE. 

...DISCUSSION...

ONGOING THUNDERSTORMS APPROACHING THE COAST OF FLORIDA WILL POSE A THREAT FOR A FEW TORNADOES/WIND GUSTS. SEE STO 222 FOR MORE DETAILS. 

THE OVERALL ENVIRONMENT ACROSS THE AREA IS FAVORABLE FOR THUNDERSTORM DEVELOPMENT, WITH 1500-4500 J/kg SBCAPE RANGE ACROSS THE AREA. DRY MID-LEVEL AIR FUNNELING INTO THE AREA WILL ALSO INCREASE DCAPE, ESPECIALLY OVER SOUTHERN AL/MS AND FL PANHANDLE, WHERE 800-1400 J/kg IS INDCATED AT THIS TIME, AND COULD INCREASE WITH TIME. ACROSS THIS AREA, SRH IS RATHER LOW, WITH THE MAIN TORNADO THREAT CONFINED TO BARRIER ISLANDS AND THE IMMEDIATE COAST FROM WATERSPOUTS. THIS DRY AIR AND STRONG CAPE VALUES ALSO SUPPORT AN ISOLATED HAIL THREAT THIS AFTERNOON. 

FOR THE CAROLINAS...STRONGER SHEAR BUT WEAKER CAPE IS NOTED DUE TO BEING ALONG OR JUST NORTH OF THE SURFACE BONDARY. STILL, A FEW ROTATING THUNDERSTORMS AND WEAK TORNADOES WILL BE POSSIBLE. A SECONDARY DCAPE MAXIMA OVER THIS REGION COULD ALSO SUPPORT A DAMAGING WIND POTENTIAL THIS AFTERNOON IF CAPE CAN INCREASE, ALLOWING FOR THUNDERSTORM DEVELOPMENT. 

ACROSS THE ENTIRE AREA, 850MB WINDS OF 220-25KTS IS PROMOTING EFFECTIVE SHEAR GENERALLY UNDER 20KTS, EXCEPT FOR THE CENTRAL GULF COAST WHERE 40KTS IS NOTED DUE TO RELATIVE LOCATION TO FRONT AND TROUGH. WHERE SHEAR OF 20-25KTS AND HIGHER IS NOTED, MULTICELL CLUSTERS AND A FEW LINEAR SEGMENTS ARE POSSIBLE, AND THIS COULD BE WHERE SEVERE WEATEHR IS MOST LIKELY.