FXUS62 KTBW 060755
AFDTBW
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAMPA BAY RUSKIN FL
255 AM EST SUN DEC 6 2009
.SHORT TERM (TODAY - TUESDAY)...CHILLY START TO THE DAY WITH
MAINLY CLEAR SKIES FOR MOST OF THE REGION...BUT SOME LOWER CLOUDS
ALREADY MOVING IN FROM THE SOUTHEAST OVER OUR SOUTHERN ZONES.
EXPECT TO SEE A GRADUAL INCREASE IN CLOUDS TODAY...AND IT COULD
VERY WELL BECOME MOSTLY CLOUDY BY NOON OR SO. SATELLITE IMAGERY
SHOWS SOME CYCLONIC TURNING IN THE LOW CLOUDS OVER SOUTH
FLORIDA...AND THE NAM DEPICTS THIS TROUGH AND WEAK LOW FAIRLY
WELL. BOTH THE GFS AND NAM BRING LOTS OF CLOUDS IN FROM THE SOUTH
AND EAST TODAY...AND THE NAM EVEN HAS SOME LOW END RAIN CHANCES
AROUND FORT MYERS. THE CLOUDS WILL PLAY A ROLE IN OUR HIGH
TEMPERATURES TODAY...AND EXPECT TO BE A DEGREE OR TWO COOLER THAN
THE 00Z MAV NUMBERS AT MOST LOCATIONS.
IT SHOULD STAY MOSTLY CLOUDY OVERNIGHT...AND THESE CLOUDS WILL
LOWER AND THICKEN WITH TIME. THE DEPTH OF THESE CLOUDS MAY ALSO
SUPPORT SOME LIGHT RAIN...ESPECIALLY OVER THE SOUTHERN HALF OF OUR
AREA. I ADDED PATCHY FOG AS WELL...BUT WITH THE CLOUD COVER AND A
BIT OF WIND...IT SHOULD NOT BECOME VERY WIDESPREAD OR DENSE. MAV
GUIDANCE SEEMS TO BE HITTING THE FOG A BIT TOO HARD BASED ON THE
ATMOSPHERE AS A WHOLE.
IT DOES LOOK LIKE WE SHOULD SEE SOME SUNSHINE RETURNING FOR
MONDAY. WEAK RIDGING ALOFT BUILDS IN FROM THE SOUTH...AND THE LOW-
LEVEL FLOW GETS QUITE LIGHT. ASSUMING WE DO SEE SOME AFTERNOON
SUNSHINE... TEMPERATURES WILL CLIMB INTO AT LEAST THE MID
70S...AND COULD EVEN BREAK 80 SOUTH OF THE TAMPA BAY AREA.
FORECAST SOUNDINGS FROM BOTH THE NAM AND GFS SHOW A BETTER CHANCE
FOR FOG MONDAY NIGHT. LIGHT NORTHEAST WINDS AND DEW POINTS NEAR
60 DEGREES WILL PROVIDE A FAVORABLE ENVIRONMENT FOR FOG...BUT WE
MAY STILL HAVE SOME CLOUD COVER AROUND WHICH WOULD HELP TO
INHIBIT DEVELOPMENT. WILL START OFF WITH PATCHY FOG EVERYWHERE
AND LET FUTURE SHIFTS TWEAK AS NEEDED.
WARMER AND MORE HUMID AIR WILL CONTINUE TO INVADE THE AREA ON
TUESDAY. I USED A BLEND OF THE MAV AND MET POPS WHICH YIELDS
ABOUT 20 PERCENT RAIN CHANCES...BUT WOULD NOT BE SURPRISED IF IT
STAYS DRY. FOR TEMPERATURES...I LEANED TOWARD THE SLIGHTLY COOLER
MAV GUIDANCE WHICH IS STILL 5 DEGREES ABOVE AVERAGE FOR THIS TIME
OF YEAR.
.LONG TERM (TUESDAY NIGHT - SATURDAY)...PROGRESSIVE SPLIT FLOW
PATTERN WILL CONTINUE ACROSS THE U.S. DURING THE LONG TERM PERIOD.
A COLD FRONT WILL MOVE THROUGH THE PANHANDLE AND INTO THE NORTHERN
PENINSULA DURING THE DAY ON WEDNESDAY AS AN INTENSE STORM SYSTEM
MOVES FROM THE OHIO VALLEY NORTHEAST INTO THE EASTERN GREAT LAKES
REGION. THE FRONT WILL THEN WEAKEN AS IT MOVES SOUTH INTO THE
NORTH CENTRAL PENINSULA WEDNESDAY NIGHT AND THURSDAY...BEFORE
STALLING OUT ACROSS THE SOUTHERN PENINSULA THURSDAY NIGHT AND
FRIDAY. SUFFICIENT MOISTURE ACCOMPANYING THE FRONT VIA MODEL
CROSS-SECTIONS WILL SUPPORT SCATTERED SHOWERS (POPS 30 PERCENT)
OVER THE NATURE COAST ON WEDNESDAY...AND ACROSS THE REMAINDER OF
REGION WEDNESDAY NIGHT INTO THURSDAY AS THE FRONT MOVES SOUTH.
DURING THURSDAY NIGHT LOW END CHANCE POPS WILL CONTINUE OVER THE
CENTRAL AND SOUTHERN FORECAST AREA IN THE VICINITY OF THE STALLING
FRONT WITH DRIER AIR MOVING INTO NORTHERN SECTIONS AS SURFACE HIGH
PRESSURE BUILDS IN OVER THE SOUTHEASTERN STATES. DURING FRIDAY AND
FRIDAY NIGHT THE SURFACE HIGH WILL SHIFT EAST OFF THE MID ATLANTIC
COAST AS THE NEXT SHORT WAVE TROUGH AND WEAK SURFACE LOW WITHIN
THE ACTIVE SOUTHERN STREAM APPROACHES FROM THE WEST...WITH THE
NEXT CHANCES FOR RAIN LATE FRIDAY NIGHT INTO SATURDAY WITH HIGHEST
POPS LIKELY ACROSS NORTHERN MOST ZONES CLOSEST TO THESE FEATURES.
TEMPERATURES ARE EXPECTED TO RUN SLIGHTLY ABOVE NORMAL THROUGH THE
PERIOD.
&&
.AVIATION...BRIEF MVFR CEILINGS WILL IMPACT FORT MYERS AND
REGIONAL SOUTHWEST TERMINALS THROUGH 06/09Z THIS
MORNING...OTHERWISE VFR IS EXPECTED AT ALL TERMINAL SITES. AFTER
06/14Z AND CONTINUING THROUGH THE REMAINDER OF THE DAY EXPECT TO
SEE BROKEN TO OVERCAST STRATO-CU CLOUDS DEVELOP AT ALL SITES...BUT
CEILING HEIGHTS IN THE FL035-040 RANGE SHOULD MAINTAIN VFR
CONDITIONS. AFTER 07/02Z TONIGHT EXPECT TO SEE VFR CONDITIONS
LOWER INTO THE MVFR RANGE AS LOW CLOUDS AND PATCHY FOG DEVELOPS
ACROSS THE AREA.
&&
.MARINE...SEAS ARE NOW DOWN TO 4 TO 5 FEET AT THE OFFSHORE BUOYS
AND WINDS ARE ALL IN THE 10 TO 15 KNOT RANGE. WILL NOT INCLUDE ANY
HEADLINES IN THIS MORNINGS FORECAST. EXPECT GENERALLY BENIGN
CONDITIONS THROUGH TUESDAY OR TUESDAY NIGHT...THEN INCREASING
SOUTH TO SOUTHWESTERLY WINDS ON WEDNESDAY AS A COLD FRONT MOVES
INTO THE GULF. THE FRONT WILL MOVE SLOWLY THROUGH OUR WATERS
WEDNESDAY NIGHT AND THURSDAY BRINGING WINDS OF AROUND 20 KNOTS AND
SEAS UP TO 7 FEET.
&&
.FIRE WEATHER...NO FIRE WEATHER CONCERNS.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 66 59 76 61 / 5 10 10 10
FMY 70 62 80 62 / 10 20 10 10
GIF 68 59 78 60 / 5 10 10 10
SRQ 68 58 77 61 / 5 20 10 10
BKV 66 52 76 55 / 5 10 10 10
SPG 65 59 75 62 / 5 10 10 10
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
SHORT TERM/MARINE/FIRE WEATHER...JILLSON
LONG TERM/AVIATION...MCMICHAEL
