Severe Thunderstorm Warning 293, NWS Jacksonville, FL

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSONVILLE FL
300 PM EDT THU AUG 31 2000

CURRENTLY...VIS IMAGERY SHOWS WIDESPREAD CU FIELD HAS FORMED ALL
OVER FA WITH SCT CONVECTION MAINLY IN SRN AND WRN PORTIONS OF FA. E
COAST SEA BREEZE FORMED AND IS MOVING INLAND WITH FAIRLY GOOD INLAND
PENETRATION SO FAR. EXPECT SEA BREEZE AND WEAK TROUGHING OVER THE
REGION TO TRIGGER MORE CONVECTION DURING THE AFTN. WATER VAPOR NEAR
ERN GA WITH TROUGHING TO THE SW OVER THE GULF OF MEXICO. WATER VAPOR
LOOP HINTS AT A WEAK DRY SLOT MOVING IN JUST S OF MARION COUNTY.

FORECAST...UPPER LEVEL LOW EXPECTED TO THE MAIN PLAYER DURING THE
PERIOD. AVN MODEL SHIFTS IT WEST IN THE SHORT TERM THEN BRINGS IT
EAST DURING THE WEEKEND. ETA AND AVN APPEAR TO BE DOING WELL WRT TO
SFC FEATURES AND PRECIP AT 18Z. APPEARS BEST MOISTURE AND OMEGA
FIELD WILL BE IN THE WRN PORTIONS OF THE FA. ALL MODELS INDEED DO
SHOW BETTER LOW LEVEL CONVERGENCE FROM ABOUT BAKER COUNTY WWD FRIDAY
AFTN AND WITH GOOD SW FLOW OFF THE GULF AND AMPLE MOISTURE
CONVECTION SHOULD NOT HAVE PROBLEM DEVELOPING. ETA FCST CALLS FOR
HIGH CAPES WELL ABOVE 3000 J/KG THERE FRI AFTN WHICH SEEM OVERDONE
GIVEN RELATIVELY WEAK LAPSE RATES AND -5 TO -6 500 MB TEMPS. WOULD
NOT RULE OUT SEV WEATHER THAT AREA ON FRI AFTN. WILL PROBABLY CARRY
GOOD CHANCE POPS MOST AREAS WITH A LITTLE LOWER POSSIBLY COASTAL GA
COUNTIES. FOR SAT...CONTINUED DEEPER MOISTURE IN OUR WRN COUNTIES
WITH BETTER LIFT PROGGED BUT HARD TO TELL WHERE TO GO PUT HIGHEST
POPS SO FOR NOW WILL GO WITH 40 PERCENT. CONVECTION INTO THE EVENING
TONIGHT AND FRI NIGHT LOOKS LIKE A GOOD BET AND WILL CARRY LOW
CHANCE MOST EVERYWHERE. FAN/FWC TEMPS LOOK REASONABLE AND WILL BLEND.

MARINE...MOSTLY LIGHT SLY WIND INDICATED FROM OBS AT THIS TIME
EXCEPT E AT THE COAST FROM SEA BREEZE. VIS IMAGERY SHOWS CU MOVING OFF
TOWARD THE NE IN THE SRN WATERS. WINDS PREDOMINATELY S TO SW DURING
THE PD AT 10-15 KT. SEAS LOWER CLOSER TO THE COAST DUE TO SHORTER
FETCH. POSSIBILITY OF SCEC CONDITIONS OFFSHORE BY FRI NIGHT AND FOR
NOW WILL HOLD OFF ON THIS FOR LATER SHIFTS TO DECIDE ON.

EXTENDED...NOT MUCH CHANGE TO CURRENT FORECAST. UPPER LEVEL LOW
INDICATED TO DRIFT WSW AFTER SUN BUT AMPLE MEAN LAYER MOISTURE REMAINS
OVER THE FA. SFC TROUGH SHOULD REMAIN TO OUR W SO CONTINUED SWLY LOW
AND MID LEVEL FLOW PREVAILS.

THANKS TLH AND MLB FOR COORD.

_PRELIM CCF
AMG 71/88/71/88 3534
SSI 73/86/74/86 2434
JAX 71/91/72/93 3534
GNV 70/89/71/90 3524 02

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

ARS