Severe Thunderstorm Warning 94, NWS Jacksonville, FL

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSONVILLE FL
1000 AM EDT SAT JUL 20 2002

CURRENTLY....MOSTLY SUNNY SKIES PREVAIL OVER MOST OF THE AREA.
CLOUDINESS FROM GULF COAST CONVECTION LINGERING OVER LOWER SUWANNEE
VALLEY. IN ADDITION...MID-LEVEL AC NOTED ON VIS SAT OVER N CWA
(COUNTY WARNING AREA). THESE CLOUDS INDICATIVE OF GOOD MID-LAYER
INSTABILITY...IN ADDITION TO PROXIMITY OF LOW AND MID LEVEL TROFFING
IN THAT AREA. SFC ANALYSIS SHOWS TROF EXTENDING FROM 1008MB SFC LOW
OFF THE MID-ATLC COAST TO 1016MB OVER CENTRAL GOMEX.

12Z SOUNDING SHOWS A BIT STRONGER LOW-LEVEL INVERSION AT ABOUT 925MB
(WILL TAKE ABOUT 91 DEG SFC TEMP TO BREAK). HOWEVER...SOUNDING ABOUT
AT MOIST AS YESTERDAY...ALONG WITH GREATER INSTABILITY (500MB TEMPS
ABOUT 2 DEG COOLER AND 850 TEMPS ABOUT 2 DEG WARMER). CAPES AT KTBW
ARE VERY HIGH (5600-5800 J/KG). THINK CONVECTION MAY BE A BIT LATER
IN DEVELOPING TODAY...BUT ONCE IT GOES THERE COULD BE SOME STRONG TO
SVR STORMS. THINK MOS COVERAGE IS A BIT UNDERDONE...SO WILL BOOST
1ST AND 2ND PERIOD POPS 10%. BEST SHOT INITIALLY WILL BE INTERIOR SE
GA...WHERE TSTMS ARE ALREADY APPROACHING FROM THE W. FLIES IN
OINTMENT ARE SEABREEZES. E COAST WILL BE LATE TO NON-EXISTENT IF LOW
LEVEL WESTERLIES MIX TO SFC (SOUNDING SHOWED OVER 20 KTS JUST OFF
THE DECK). ALSO...WEST COAST SEABREEZE...WHICH WOULD NORMALLY
PREDOMINATE IN THIS SITUATION...WILL BE A LITTLE LATER IN FORMING
DUE TO CLOUD COVER ALONG THE GULF COAST (ALTHO DIFFERENTIAL HEATING
AND OLD OUTFLOWS MAY HELP THERE). STORMS THAT DO DEVELOP WILL DRIFT
BACK TO THE SW...MAYBE GIVING E COAST A BETTER SHOT AT CONVECTION
LATE.

TEMPS LOOK OKAY...MAY BUMP UP A DEG OR TWO IN A FEW AREAS...
ESPECIALLY TOWARD THE E COAST.

MARINE...WILL BUMP UP WINDS A BIT...ALONG WITH INDICATING SW-W.
OTHERWISE...LITTLE CHANGE.

.JAX...
.GA...NONE.
.FL...NONE.

CARROLL/BOONE

FLZ020>025-030>033-035>038-040-GAZ132>136-149>154-162>166-202200-

NORTHEAST FLORIDA/SOUTHEAST GEORGIA HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE JACKSONVILLE FL
1215 PM EDT SAT JUL 20 2002

...HEAT INDICES BETWEEN 103 AND 108 DEGREES THIS AFTERNOON...
...ISOLATED SEVERE THUNDERSTORMS POSSIBLE...

TEMPERATURES WILL CLIMB TO BETWEEN 94 TO 98 DEGREES IN MOST INLAND
LOCATIONS...RESULTING IN HEAT INDICES BETWEEN 103 AND 108 DEGREES
DURING THE AFTERNOON AND EARLY EVENING. IF ENGAGED IN OUTDOOR
ACTIVITIES...TAKE FREQUENT BREAKS IN SHADED AREAS AND DRINK PLENTY
OF NON-ALCOHOLIC BEVERAGES.

SCATTERED THUNDERSTORMS ARE EXPECTED TO DEVELOP THIS AFTERNOON. A
FEW OF THESE THUNDERSTORMS WILL BECOME SEVERE FROM MID-AFTERNOON
THROUGH THE EVENING HOURS. STRONGEST STORMS WILL PRODUCE HAIL AND
WIND GUSTS OVER 40 MPH. ALL STORMS WILL CONTAIN LOCALLY HEAVY RAIN
AND FREQUENT LIGHTNING STRIKES. SPOTTERS ARE REQUESTED TO
SELF-ACTIVATE AS CONDITIONS WARRANT.

FOR ADDITIONAL INFORMATION...VISIT THE NATIONAL WEATHER SERVICE IN
JACKSONVILLE WEBSITE ON THE INTERNET AT WWW.SRH.NOAA.GOV/JAX.

CARROLL