SPC Issues Severe Weather Risk across Alabama

As a dynamic storm system moves closer to the state, the SPC has issued a slight risk for severe weather for much of north-central Alabama for today. This includes Birmingham, Tuscaloosa, Huntsville, Gadsden, and Anniston. The risk area is outlined in green and includes portion of central Mississippi and northeastern Louisiana as well.

There is a threat for isolated damaging winds and tornadoes.

A very strong cold front moving into the state will be enhancing the uplift across the state. A very warm and moist air mass is in place across the state, and with these ingredients coming together there will be a threat of severe weather. The SPC is currently determining whether or not to issue a watch for portions of the state.

SUMMARY…A CONDITIONAL THREAT FOR ISOLD DMGG WINDS AND A TORNADO OR
TWO APPEARS TO BE INCREASING ACROSS PORTIONS OF THE LOWER MS RIVER
VALLEY AND EVENTUALLY SPREADING NEWD INTO NWRN PORTIONS OF AL.
STORMS ARE EXPECTED TO DEVELOP/INCREASE IN INTENSITY DURING THE
17-22Z TIMEFRAME.

DISCUSSION…LATEST SUBJECTIVE SURFACE ANALYSIS SHOWS UPPER 60S TO
NEAR 70 DEG DEWPOINTS SPREADING NWD EITHER SIDE OF THE LA/MS BORDER
WITH UPPER 60S /AS OF 16Z/ ADVECTING NEWD INTO NERN MS AND NWRN AL.
VISIBLE SATELLITE IMAGERY DURING THE PAST FEW HOURS SHOWS THINNING
CLOUD COVER OVER CNTRL MS INTO W-CNTRL AL AS TEMPS RISE INTO THE
LOWER 70S AND THIS HEATING IS CONTRIBUTING TO FURTHER
DESTABILIZATION. OF PARTICULAR NOTE…THE 12Z RUN OF THE RAP MODEL
UNDER-FORECASTED SURFACE DEWPOINTS THIS MORNING /ROUGHLY 2 DEG F/
AND MAGNITUDE OF LOW-LEVEL SHEAR /COMPARED TO THE 12Z JAN RAOB/.
DESPITE SOMEWHAT MEAGER LAPSE RATES…MODIFYING THE 12Z JAN RAOB FOR
MID 70S TEMP/70 DEWPOINT BOOSTS MLCAPE TO AROUND 800 J/KG AND
REDUCES SBCINH WITHIN A VERY MOIST LOW LEVEL AIRMASS. MORE THAN
ADEQUATE SHEAR PROFILES ALONG WITH CONTINUED LOW-LEVEL CONFLUENT
REGIME AHEAD OF THE SEWD-MOVING COLD FRONT WILL LEND SUPPORT FOR
MAINLY DIURNALLY-PEAKING STORMS AND AN INCREASED PROPENSITY FOR
GRADUAL STORM INTENSIFICATION AND ISOLD LOW-LEVEL SUPERCELL
ROTATION–PERHAPS CAPABLE OF

Category: Alabama's Weather, Severe Weather