Severe Thunderstorm Warning 111, NWS Tallahassee, FL

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TALLAHASSEE FL
300 PM EDT THU JUL 20 2000

WELL WE REACHED 100 DEGREES WHICH TIED DAILY TALLAHASSEE RECORD
PREVIOUSLY SET IN 1986. FOR ALL STATISTICS BUFFS...THIS MARKED THE
6TH CONSECUTIVE DAY OF AT OR ABOVE 100 DEGREE DAYS HERE (5TH
CONSECUTIVE DAY WHERE A RECORD OF WAS TIED OR EXCEEDED). THE LOCAL
RECORD FOR CONSECUTIVE DAYS AT OR ABOVE 100 DEGREE DAYS IS SEVEN
(JUNE 17-23 1998) AND WE WILL BE BORDERLINE 100 DEGREES TOMORROW. SO
STAY TUNED. DURING LATE MORNING IT LOOKED LIKE WE HAD POTENTIAL TO
REACH 104 DEGREES THE ALL TIME DAILY HIGH...BUT ALAS A SEA BREEZE
FORMED DURING EARLY AFTERNOON ACROSS THE CENTRAL BIG BEND...INCLUDING
TALAHASSEE AND THE WINDS SHIFTED TO SE AND LOCAL TEMPS UNDER GOOD
OUTFLOW BOUNDARY COOLING "PLUMMETED" TO 80 DEGREES. VERY HEAVY RAINS
SRN LEON/WAKULLA COUNTY AND RADAR ESTIMATED 3-4 INCHES IN LAST HOUR
PLUS NECESSITATING AN URBAN AND SMALL STREAM ADVISORY. CONVECTION
LINE WITH DANGEROUS LIGHTNING...MARBLE SIZE HAIL AND MAXIMUM OUTFLOW
WINDS TO 60 KNOTS WITH SPECIAL MARINE WARNING ISSUED FOR IMMEDIATE
NEAR SHORE WATERS AND SVR TSTM WARNING FOR LEON/WAKULLA COUNTY

LOOKING BEYOND TONIGHT...
THERE ARE DEFINITE INDICATIONS THAT SYNOPTIC PATTERN TO CHANGE. AS
RIDGE OVER SE U.S. CONTINUES TO RETROGRADE WESTWARD...ALLOWING VORTS
TO ROLL AROUND SYSS CARVING OUT TROUGH AND ALLOWG IT TO DIG INTO SE
CONUS. THIS INDICATED BY ALL MODELS WITH LOWERING HGTS/THICKNESS AND
COOLING TEMPERATURES. AT SURFACE...LOW OFF SOUTH CAROLINA COAST WITH
WEAK FRONT STRETCHING TO NEAR FLA/GA BORDER. THIS FRONT WILL WEAKEN
AND MAY DRIFT SWD BUT WILL LIKELY DISSIPATE. A SECOND FRONT ACROSS
CENTRAL CONUS WILL INCH SLOWLY SEWD TOWARDS LOCAL AREA AND WITH
SUPPORT OF UPPER VORTS MOVE CLOSE TO AND LIKELY STALL ACROSS SE GA
SWWD THRU NE GULF ON LATE MONDAY. AHEAD OF BOUNDARY AND BEGINNING
TOMORROW...INCREASING DVNGNC ALOFT...INCREASG SFC-H85 MOISTURE AND
INCREASINGLY UNSTABLE SOUNDINGS. PER SATELLITE...NEXT SHORT WAVE TO
ROLL ACROSS CWA MID AFTERNOON FRIDAY HELPING TO KICK UP CONVECTION.

LOCALLY IT APPEARS THAT SEA BREEZE TYPE 8 (1000-700 MB NW FLW WILL
SHIFT TO WETTER TYPE 4 (WSW FLOW) BY LATE FRIDAY AFTERNOON. THIS
FAVORS EARLY AFTERNOON SCENARIO SIMILIAR TO TODAY BUT UNDER MORE WLY
FLOW BY MID AFTERNOON...ACTIVITY WILL LIKELY PUSH EWD TOWARD VLD
AND/OR SE TOWARDS SE BIG BEND. EITHER WAY NGM POPS MAY BE UNDER
FORECASTG AND ACTUAL SCENARIO MAY BETTER MIRROR SEA BREEZE
CLIMATOLOGY...NAMELY A MERGING OF TYPE 8 AND 4 WITH TIP TO TYPE 4 OR
40-50 PERCENT ACROSS SRN THIRD OF BIG BEND AND 30-40 PERCENT ACROSS
REST OF FLORIDA AND MOST OF ALA/GA.

EXTENDED MODELS IN AGREEMENT THAT TROF WILL CONTINUE TO DIG..AND
LOCAL AREA TO BE E OF AXIS BY SUNDAY. GOOD CHANCE OF SHOWERS NAD
THUNDERSTORMS AND COOLING TEMPS DOWN TO CLIMO THRU EXTENDED PERIOD.

MARINE: W/SW WINDS WITH SEAS 2-3 FEET LOOK GOOD NEXT TO DAYS.
CONCERN REMAINS SWD SHIFT OF SEA BREEZE TOMORROW..WHICH AGAIN MAY
IMPACT NEARSHORE WATERS CONVECTIONS...ESPECIALLY ACROSS APALAC BAY.

FIRE WEATHER: RH TO INCREASE SUFFICIENTLY TOMORROW TO PUT ALA/FL
ABOVE WARNING/WATCH CRITERIA.

PRELIM NUMBERS...

TLH  78 100 77 95 2535
PFN  80  95 80 90 2435
DHN  77 100 76 95 1434
ABY  76  99 75 93 1324
VLD  75  99 75 95 2434

.TLH...
AL...RED FLAG WARNING UNTIL SUNSET.
GA...HEAT ADVISORY SOUTHERN TIER ZONES UNTIL SUNSET (GAZ155>160).
FL...HEAT ADVISORY ALL ZONES UNTIL SUNSET.

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ALZ065>069-FLZ007>019-026>029-034-GAZ120>131-142>148-155>161-GMZ700-
701-750-755-770-775-790-791-201900-

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE TALLAHASSEE FL
208 PM EDT THU JUL 20 2000

DURING THE EARLY AFTERNOON...THE COMBINATION OF STRONG INSOLATION
GENERATING AN UNSTABLE AIR MASS WAS INTERACTING WITH THE NORTHWARD
DRIFTING SEA BREEZE AND SOUTHWARD DRIFTING THUNDERSTORMS TO
GENERATE A LINE OF STRONG THUNDERSTORMS ACROSS THE COASTAL FLORIDA
BIG BEND AND PANHANDLE COUNTIES. THESE WERE DRIFTING TOWARDS THE
ADJACENT COASTAL WATERS. SOME OF THESE WILL LIKELY GROW INTO SEVERE
THUNDERSTORMS DURING THE REST OF THIS AFTERNOON AND INTO THE
EVENING. LIKEWISE ADDITIONAL POTENTIALLY SEVERE THUNDERSTORMS MAY
DEVELOP ACROSS OTHER SECTIONS OF FLORIDA.

EMERGENCY MANAGERS AND SPOTTERS SHOULD CLOSELY MONITOR THE WEATHER
AND REPORT ANY SEVERE WEATHER OR POTENTIALLY SEVERE WEATHER TO THE
NATIONAL WEATHER SERVICE IN TALLAHASSEE.

FOR ADDITIONAL WEATHER INFORMATION...VISIT THE NATIONAL WEATHER
SERVICE IN TALLAHASSEE ON THE INTERNET AT WWW.SRH.NOAA.GOV/TLH OR
TUNE INTO NOAA WEATHER RADIO.

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