Severe Thunderstorm Watch Likely Soon

AREAS AFFECTED…NRN AND CNTRL MS / CNTRL AND S-CNTRL AL / W-CNTRL
GA

CONCERNING…SEVERE POTENTIAL…SEVERE THUNDERSTORM WATCH LIKELY

VALID 171634Z – 171830Z

PROBABILITY OF WATCH ISSUANCE…80 PERCENT

SUMMARY…SCATTERED CONVECTIVE INITIATION IS ANTICIPATED BETWEEN
17-19Z. SCATTERED WIND DAMAGE FROM SEVERE MULTICELLULAR STORM
CLUSTERS IS FORECAST. SEVERE HAIL WILL BE POSSIBLE WITH THE
STRONGER UPDRAFTS. A SEVERE THUNDERSTORM WATCH IS LIKELY ACROSS
PARTS OF AL/MS BUT IT REMAINS UNCLEAR WHETHER A WATCH IS NEEDED IN
GA.

DISCUSSION…VISIBLE IMAGERY SHOWS A SWELLING CU FIELD ACROSS NRN MS
EWD ACROSS AL AND INTO NWRN GA. SURFACE OBSERVATIONS SHOW TEMPS
HAVE WARMED TO THE LOWER 90S AT 16Z AND SURFACE DEWPOINTS RANGE FROM
THE MID-UPPER 70S. THE 12Z RAOBS FROM JAN AND BMX EXHIBITED STRONG
BUOYANCY /2500 J PER KG MLCAPE/ AND LOWEST 100-MB MEAN MIXING RATIOS
16.5-17.0 G/KG. STRONG HEATING THIS MORNING HAS PROBABLY RESULTED
IN EVAPOTRANSPIRATION AND AUGMENTED MIXING RATIOS INTO THE 17-18
G/KG RANGE. FURTHERMORE…A RELATIVELY COOL H5 PROFILE RANGING FROM
-10 DEG C ON THE JAN RAOB TO -8 DEG C AT FFC WILL SUPPORT LARGE HAIL
GROWTH WITH THE STRONGER UPDRAFTS.

A COLD FRONT CURRENTLY ANALYZED OVER WRN TN EXTENDING ESEWD INTO NRN
GA WILL PROBABLY SERVE AS A FOCUS FOR THUNDERSTORM INITIATION DURING
THE NEXT FEW HOURS. MODIFYING THE 12Z AREA RAOBS IMPLIES LITTLE
MLCINH REMAINS. ADDITIONAL HEATING WILL RESULT IN A VERY UNSTABLE
BOUNDARY LAYER /MLCAPE RANGING FROM 3500-4000 J PER KG OVER MS/AL TO
3000 J PER KG OVER GA/. DESPITE ONLY WEAK TO MODEST WNW TO NNWLY
TROPOSPHERIC FLOW…THE MAGNITUDE OF BUOYANCY/MOISTURE WILL LIKELY
RESULT IN SEVERE MULTICELLS DEVELOPING DURING THE AFTERNOON.
WATER-LOADED MICROBURSTS CAPABLE OF SEVERE-WIND GUSTS/DAMAGE ARE
LIKELY LATER THIS AFTERNOON. UPSCALE GROWTH INTO ONE OR MORE
CLUSTERS WILL LIKELY CONCENTRATE WIND DAMAGE SWATHS.

Tags: ANC

Category: Alabama's Weather, Severe Weather