FXUS62 KMFL 041837
AFDMFL

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MIAMI FL
137 PM EST FRI DEC 4 2009

.AVIATION...
BASED ON LATEST RADAR TRENDS...FEEL THAT LIGHT/MODERATE SHRA
ACTIVITY WILL BE CONFINED TO APF/PBI FOR REMAINDER OF
AFTERNOON...AND WILL INCLUDE VCSH FOR ONLY THESE TERMINALS.
OTHERWISE...EXPECT PREVAILING MVFR CONDS WITH BKN SC DECK NOW
BEING REPORTED AT MOST TERMINALS AND CIGS GENERALLY RANGING FROM
1500-2500 FT. SKY CONDS MAY IMPROVE FROM LATE AFTERNOON THRU EARLY
EVENING...BUT EXPECT DETERIORATION ONCE AGAIN EARLY SATURDAY
MORNING AS CONVECTION DEVELOPS INVOF SURFACE LOW MOVING ACROSS
CENTRAL FLORIDA. THREAT FOR SIGNIFICANT TSRA DEVELOPMENT WILL
INCREASE AS EARLY AS 06Z APF/PBI...WITH CHANCES INCREASING FURTHER
TO THE SOUTH (BROWARD AND MIAMI-DADE TERMINALS) BETWEEN 09-11Z.
WILL UTILIZE VCTS/CB FOR NOW AND INDICATE MVFR CIGS...WITH GUSTY
SSE WINDS PREVAILING OUTSIDE OF STORMS. PREFRONTAL TROUGH WILL BE
PUSHING ACROSS SOUTH FLORIDA AFTER DAWN...WITH WINDS SHIFTING TO
SOUTHWEST AND INCREASING TO 15G25 KNOTS. BEST ESTIMATE ON TIMING
IS 14Z APF/PBI...16Z FLL/FXE...AND 17Z MIA/TMB/OPF. ALTHOUGH CIGS
MAY IMPROVE TO VFR DURING THIS PERIOD...WILL MAINTAIN VCTS/CB AS
THERE AS UNCERTAINTY ON WHEN STORM CHANCES WILL END.

70/DD

&&

.PREV DISCUSSION... /ISSUED 1035 AM EST FRI DEC 4 2009/

UPDATE...THE FRONTAL BOUNDARY HAS LIFTED A LITTLE NORTH ALREADY
THIS MORNING AND IS CURRENTLY FROM AROUND WEST PALM BEACH TO
AROUND NAPLES, AND THE BOUNDARY IS EXPECTED TO CONTINUE ITS SLOW
CREEP NORTHWARD THROUGH THE EVENING. A GOOD AMOUNT OF ISENTROPIC
LIFT WILL CONTINUE THROUGH THE NIGHT ACROSS PORTIONS OF THE LAKE
AREA AND CENTRAL FL SO ATTM INCREASED THE POPS A BIT. OTHERWISE,
THE REST OF THE FORECAST REMAINS UNCHANGED. /TINGLER

.PREV DISCUSSION... /ISSUED 447 AM EST FRI DEC 4 2009/

DISCUSSION...SHALLOW COLD FRONT LOCATED OVER MIAMI DADE COUNTY
EARLY THIS MORNING WILL MOVE UP TO THE LAKE OKEECHOBEE AREA
TONIGHT AND THEN GET A FINAL PUSH SOUTH OF THE AREA SATURDAY
AFTERNOON. HIGHEST POPS WILL BE LIKELY TO CATEGORICAL MAINLY NORTH
AND NORTHWEST AREAS DUE TO MAINLY OVERRUNNING THROUGH TONIGHT.
EXPECT CHANCE OF POPS SOUTHEAST AREAS. THEN AS THE FRONT MOVES
THROUGH SATURDAY, 60 TO 80 PERCENT POPS CAN BE EXPECTED WITH THE
FRONT AND THE RAIN WILL TAPER OFF LATE IN THE DAY SATURDAY. THE
MAIN STORY WITH THE FRONT MOVING NORTH LATER TONIGHT IS THE
POSSIBILITY OF ELEVATED THUNDERSTORMS AND THE WIND PROFILES LOOK
FAVORABLE FOR TORNADOES NORTH OF THE FRONT. AS THE FRONT MOVES
SOUTH SATURDAY MORNING, THE HELICITY LESSENS AND THE CHANCES OF
TORNADOES DECREASES AND THE MAIN THREAT WITH THE FRONT WILL BE
STRONG STRAIGHT LINE WIND GUSTS. AFTER THE FRONT PASSES, HIGH
PRESSURE BUILDS IN FROM THE NORTHWEST AND A LOW FORMS OVER THE
CAROLINA WATERS AND MOVES NORTHEAST. THE HIGH PRESSURE MOVES INTO
THE ATLANTIC EAST OF THE MID ATLANTIC STATES SUNDAY NIGHT. WINDS
WILL QUICKLY VEER AROUND TO THE SOUTH BY TUESDAY AND SOUTHWEST
WEDNESDAY AS ANOTHER COLD FRONT APPROACHES THE AREA. THE COOL AIR
ASSOCIATED WITH THE FRONT WILL BE SHORT LIVED AND THE COOLEST
MORNING WILL BE SUNDAY MORNING. THE NEXT FRONT WILL MOVE THROUGH
ON THURSDAY WITH ONLY A CHC OF POPS. DON'T EXPECT VERY COOL AIR
BEHIND THIS FRONT EITHER.

MARINE...WINDS WILL BE LIGHT EAST THEN BECOME SOUTHEAST TO SOUTH
AS THE FRONT MOVES NORTH. WINDS WILL BECOME NORTHERLY AS THE
FRONT PASSES LATER SATURDAY AND SCA CONDITIONS MAY DEVELOP BY
SATURDAY OVER THE GULF WATERS AND SCEC CONDITIONS OVER THE
ATLANTIC WATERS SATURDAY NIGHT. WINDS WILL DECREASE BY SUNDAY AND
THEN VEER QUICKLY TO THE SOUTHEAST TUESDAY. SWELLS WILL BE
PRODUCED FROM THE LOW AND REACH THE PALM BEACH WATERS SUNDAY NIGHT
AND LAST THROUGH AT LEAST TUESDAY NIGHT. EXPECT 2 TO 4 FOOT SWELLS
SUNDAY OVER THE GULF WATERS.

FIRE WEATHER...NO CONCERNS HERE AS THE MINIMUM RELATIVE HUMIDITIES
WILL BE ABOVE CRITICAL VALUES.

&&

.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH  82  70  78  58 / 60 60 80 10 
FORT LAUDERDALE  83  72  82  62 / 40 50 60 10 
MIAMI            84  72  82  63 / 40 40 60 10 
NAPLES           80  70  75  55 / 90 70 70 10 

&&

.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.

&&

$$

LONG TERM...04/AT
SHORT TERM/AVIATION...70/DD