FXUS62 KTBW 260633
AFDTBW
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAMPA BAY RUSKIN FL
135 AM EST SAT DEC 26 2009
.SHORT TERM (TODAY-MONDAY)...SURFACE HIGH PRESSURE WILL BUILD OVER
THE SOUTHEAST U.S. AND FLORIDA TODAY WITH MUCH DRIER COOLER AIR
ADVECTING ACROSS THE REGION. SUBTROPICAL JET REMAINS ACROSS THE
GULF OF MEXICO AND FLORIDA WHICH WILL CONTINUE TO STREAM HIGH LEVEL
CLOUDINESS OVER WEST CENTRAL AND SOUTHWEST FLORIDA...WITH ANOTHER
U/L DISTURBANCE MOVING OVER THE GULF OF MEXICO TONIGHT. THIS WILL
CREATE OVERRUNNING PRECIP OVER THE CENTRAL GULF OF MEXICO. BUT AS
IT PUSHES EAST INTO DRIER AIRMASS OVER FLORIDA SUNDAY NIGHT AND
MOVES INTO CONFLUENT U/L FLOW...RAINFALL WILL DECREASE WITH ONLY A
CHANCE OF LIGHT RAIN SUNDAY AND SUNDAY NIGHT. SECONDARY COLD FRONT
WILL PUSH ACROSS WEST CENTRAL AND SOUTHWEST FLORIDA ON MONDAY
REINFORCING THE COLD AIRMASS OVER THE FORECAST AREA. TEMPERATURES
WILL RUN BELOW CLIMATIC NORMALS THROUGH EARLY NEXT WEEK.
.LONG TERM (MONDAY NIGHT THROUGH FRIDAY)...HIGH PRESSURE WILL MOVING
BY TO THE NORTH OF OUR REGION MONDAY NIGHT THROUGH WEDNESDAY WILL
KEEP DRY CONDITIONS IN PLACE AND ALLOW FOR A GRADUAL WARMING TREND.
BY WEDNESDAY...MOST LOCATIONS WILL REACH AT LEAST 70 DEGREES WITH
SOME MID 70S OVER OUR SOUTHWESTERN ZONES.
MODELS STILL OFFER DIFFERING SOLUTIONS FOR THE NEXT SYSTEM TO AFFECT
OUR AREA THURSDAY AND FRIDAY. THE GLOBAL MODELS DO AGREE THAT WE
WILL SEE A DEEPENING EASTERN U.S. TROUGH FOR THE LAST HALF OF THE
WEEK. THIS WILL ALMOST SURELY BRING A COLD FRONT THROUGH THE REGION
WITH AT LEAST A CHANCE OF RAIN AS IT DOES SO. THE GFS IS THE FASTEST
MODEL...BRINGING SHOWERS INTO THE AREA ON THURSDAY...THEN STALLING
THE FRONT FOR 12 HOURS OR SO OVER SOUTH FLORIDA BEFORE CLEARING THE
AREA LATE FRIDAY. THE 12Z ECMWF AND 18Z DGEX ARE SLOWER...BRINGING
THE MAIN AREA OF RAIN THROUGH ON FRIDAY LEAVING THURSDAY DRIER. AT
THIS TIME...THERE IS NO CLEAR REASON TO CHOOSE ONE SOLUTION OVER THE
OTHER. THE BEST COURSE OF ACTION AT THIS TIME WOULD BE TO INCREASE
RAIN CHANCES ON THURSDAY OUT OF RESPECT FOR THE GFS AND KEEP AT
LEAST SOME RAIN CHANCES IN THROUGH THE DAY ON FRIDAY.
$$
AVIATION...EXPECTING MAINLY VFR CONDITIONS NEXT 24 HOURS BUT SOME
CONCERN FOR LOW CLOUDS OR FOG TOWARD SUNRISE WHICH COULD REDUCE
VISIBILITIES TO AROUND 3 MILES. CONFIDENCE NOT HIGH ENOUGH TO
INCLUDE IN TAFS AT THIS TIME.
&&
.MARINE...WINDS AND SEAS WILL GRADUALLY DIMINISH TODAY AND TONIGHT
OVER THE WATERS AS THE GRADIENT GRADUALLY WEAKENS. HIGH PRESSURE
WILL HOLD OVER THE WATERS THROUGH WEDNESDAY. WINDS AND SEAS WILL
INCREASE WEDNESDAY NIGHT AND THURSDAY WITH POSSIBLE SMALL CRAFT
ADVISORY CONDITIONS DEVELOPING AHEAD OF A COLD FRONT.
&&
.FIRE WEATHER...RELATIVE HUMIDITY VALUES MAY DROP BELOW 35 PERCENT
THIS AFTERNOON AND SUNDAY AFTERNOON OVER PORTIONS OF THE NATURE
COAST...BUT DURATIONS WILL REMAIN LESS THAN FOUR HOURS.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 64 47 64 51 / 10 10 30 20
FMY 70 53 72 58 / 10 10 20 20
GIF 67 46 65 49 / 10 10 30 20
SRQ 65 48 66 52 / 10 10 30 20
BKV 62 38 61 38 / 10 10 30 20
SPG 63 51 65 53 / 10 10 30 20
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
SHORT TERM/MARINE/FIRE WEATHER...13/OGLESBY
LONG TERM/AVIATION...63/JILLSON
