Severe Thunderstorm Warning 239, NWS Jacksonville, FL

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSONVILLE FL
221 PM EDT WED AUG 9 2000

SHORT TERM...
UPPER FLOW PATTERN ACROSS THE CONTIGUOUS UNITED STATES WILL
BECOME AMPLIFIED AS LARGE HIGH PRESSURE CENTER OVER THE SOUTHEAST
STATES RETROGRADES WEST AND BLENDS WITH THE SECONDARY HIGH PRESSURE
CENTER OVER THE CENTRAL PLAINS. THIS WILL RESULT IN A BROAD TROF
DEVELOPING OVER THE EASTERN SEABOARD AS WELL AS BECOMING A MAJOR
PLAYER WITH TROPICAL DEPRESSION NUMBER 4 NORTH OF THE BAHAMAS. REFER
TO LATEST ADVISORY FROM THE TROPICAL PREDICTION CENTER.

IN RESPONSE TO UPPER HIGH SHIFTING WEST...UPPER LEVEL WINDS OVER OUR
REGION WILL SHIFT TO THE WEST THEN NORTHWEST...ADVECTING IN DRIER AND
SOMEWHAT MORE STABLE AIR. A SURFACE LOW ASSOCIATED WITH THE
AFOREMENTIONED TROF WILL SWING SOUTH INTO NORTHERN GEORGIA LATE
FRIDAY WITH LOW LEVEL WINDS BECOMING MORE SOUTHERLY. THIS SHOULD
PRECLUDE A DOMINANT SEA-BREEZE WITH GREATEST CONCENTRATION ACROSS THE
INTERIOR PORTIONS OF THE CWA.

FOR TONIGHT...EVENING WIDELY SCATTERED CONVECTION WILL GIVE WAY TO
PARTLY CLOUDY SKIES. WEAK RIDGING NEAR THE SURFACE WILL AID IN
PATCHY LATE NIGHT INTO EARLY MORNING FOG.

THURSDAY AND THURSDAY NIGHT...EASTERLY WAVE OVER THE CARIBBEAN
WILL SHIFT NORTHEAST INTO THE EASTERN GULF OF MEXICO. AT THE SAME
TIME...DRIER AIR BEGINS TO FILTER INTO THE REGION FROM THE NORTHEAST.
GREATEST COVERAGE OF SHOWERS AND THUNDERSTORMS WILL OCCUR OVER OUR
WESTERN ZONES IN VICINITY OF EASTERLY WAVE AND HIGHEST PRECIPITABLE
WATER VALUES. LOOK FOR ACTIVITY TO QUICKLY DISSIPATE WITH LOSS OF
DAYTIME HEATING. TROPICAL DEPRESSION NUMBER FOUR BEGINS TO SHIFT
NORTH BY THURSDAY NIGHT OVER THE CENTRAL FLORIDA OFFSHORE WATERS.

FRIDAY...TROPICAL DEPRESSION NUMBER 4 IS FORECAST TO TRACK
NORTHEAST OVER THE WESTERN ATLANTIC. GIVEN THIS FORECAST...MAY SEE
SUFFICIENT SUBSIDENCE TO INHIBIT WIDESPREAD CONVECTION ACROSS
FLORIDA ZONES. SURFACE FRONT IS PROGGED TO MOVE SOUTH INTO CENTRAL
GEORGIA...THEREFORE WOULD EXPECT GREATEST COVERAGE TO OCCUR OVER
GEORGIA ZONES.

EXTENDED...SURFACE LOW AND ASSOCIATED FRONT WILL MEANDER SOUTH
FRIDAY NIGHT INTO MONDAY FOR CHANCE OF MAINLY AFTERNOON INTO
EVENING SHOWERS AND THUNDERSTORMS.

COASTAL WATERS...SHOULD SEE INCREASE IN WIND/SEAS THROUGH THE PERIOD
AS TROPICAL DEPRESSION NUMBER 4 SLOWLY EDGES WEST THEN TOWARDS THE
NORTH. NO HEADLINES AT THIS TIME...HOWEVER WILL LIKELY SEE SMALL
CRAFT EXERCISE CAUTION CONDITIONS OVER THE OFFSHORE WATERS BY LATE
FRIDAY.

THANKS FOR THE COORDINATION CALL MLB.

PRELIM...
AMG 73/94/72/95 2323
SSI 75/90/75/91 2323
JAX 73/94/72/95 2323
GNV 72/94/72/95 2524 16

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

FLZ020>025-030>033-035>038-040-GAZ132>136-149>154-162>166-092000-

NORTHEAST FLORIDA/SOUTHEAST GEORGIA HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE JACKSONVILLE FL
1200 PM EDT WED AUG 9 2000

...SCATTERED AFTERNOON AND EVENING THUNDERSTORMS...

A RIDGE OF HIGH PRESSURE OVER THE AREA WILL WEAKEN THIS AFTERNOON.
THE ATMOSPHERE WILL BECOME MORE UNSTABLE AND SCATTERED
THUNDERSTORMS ARE EXPECTED THROUGH THE EVENING.
THE SYNOPTIC FLOW CONTINUES TO BE LIGHT...THEREFORE
THE THUNDERSTORMS WILL FIRST FORM NEAR THE SEABREEZE ALONG THE
COAST AT AROUND 2 PM AND SPREAD FURTHER INLAND DURING THE COURSE
OF THE AFTERNOON INTO THE EVENING. THE STEERING WINDS WILL BE FROM THE NORTH
AND NORTHEAST AND STORMS THAT FORM ALONG THE COAST WILL MOVE INLAND AND
TO THE SOUTH.

A COUPLE OF STORMS COULD BRIEFLY BECOME SEVERE WITH STRONG
AND DAMAGING WINDS AND HAIL THE MAIN THREATS. ALL OF THE
STORMS WILL BE CAPABLE OF FREQUENT DEADLY CLOUD TO GROUND
LIGHTNING AND LOCALLY HEAVY RAIN OF 2 TO 3 INCHES.

TEMPERATURES ARE EXPECTED TO REACH THE LOWER TO MID 90S BY MID
AFTERNOON AND WITH THE HUMIDITY COMBINED WILL MAKE IT FEEL MORE LIKE
100 TO 105 DEGREES.

DUE TO THE POSSIBILITY OF SEVERE WEATHER...STORM SPOTTERS SHOULD BE
ALERT FOR POSSIBLE ACTIVATION THIS AFTERNOON AND EVENING.

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

$$^

DEESE