Red Flag Warning 12, NWS Tampa Bay, FL

AREA FORECAST DISCUSSION...CORRECTED
NATIONAL WEATHER SERVICE TAMPA BAY RUSKIN FL
411 AM EST FRI MAR 4 2011

CORRECTED FOR LONG TERM AND AVIATION SECTIONS

.SHORT TERM (TODAY-SUNDAY)...
IN THE MID/UPPER LEVELS A TROUGH WILL MOVE ACROSS THE CENTRAL AND
EASTERN U.S. DURING THE PERIOD. MEANWHILE STRONG HIGH PRESSURE
ALONG THE U.S. EAST COAST WILL SHIFT OUT INTO THE ATLANTIC OCEAN
TODAY AND TONIGHT WITH A STORM SYSTEM DEVELOPING OVER THE CENTRAL
U.S. SHIFTING ACROSS THE EASTERN U.S. SATURDAY AND SUNDAY.

FOR TODAY AND TONIGHT THE BREEZY EASTERLY FLOW WILL PERSIST UNDER
PARTLY CLOUDY SKIES. TEMPERATURES WILL REMAIN ABOVE NORMAL WITH
HIGHS TODAY IN THE UPPER 70S TO LOWER 80S AND LOWS TONIGHT MID 50S
TO LOWER 60S.

ON SATURDAY THE FLOW WILL SHIFT TO SOUTHEAST AND DIMINISH WITH A
SEA BREEZE DEVELOPING ALONG THE COAST FROM AROUND SARASOTA
NORTHWARD. SKIES WILL REMAIN PARTLY TO MOSTLY SUNNY WITH
TEMPERATURES REMAINING ABOVE NORMAL IN THE UPPER 70S TO MID 80S.

SATURDAY NIGHT INTO SUNDAY A COLD FRONT ASSOCIATED WITH THE STORM
SYSTEM WILL APPROACH AND MOVE INTO THE FORECAST AREA. TIMING OF
BOUNDARY HAS BEEN VARYING BY 6 TO 12 HOURS IN THE GFS...WHILE
ECMWF HAS BEEN PRETTY CONSISTENT. HOWEVER...THE LATEST GFS TIMING
IS NOW PRETTY CLOSE TO THE ECMWF. OVERALL IT LOOKS LIKE CLOUDS
AND SOME SHOWERS WILL MOVE INTO THE REGION LATE SATURDAY NIGHT AND
CONTINUE INTO SUNDAY. MODELS ARE INDICATING SOME INSTABILITY WITH
LIFTED INDEX VALUES DROPPING TO -2 TO -3...BUT WIND FIELDS ARE NOT
THAT IMPRESSIVE WITH WIND SPEEDS BETWEEN 925 AND 700 MB LESS
THAN 30 KNOTS AND HELICITY VALUES REMAINING LESS THAN 150 M2/S2.
THEREFORE...BIGGEST THREAT FROM ANY STORMS THAT DO FORM WILL BE
LOCALLY HEAVY RAIN...BRIEF GUSTY WINDS AND OCCASIONAL LIGHTNING.
TEMPERATURES WILL CONTINUE TO BE ABOVE NORMAL SATURDAY NIGHT AND
SUNDAY.

.LONG TERM (SUNDAY NIGHT-THURSDAY)...
THE EXTENDED FORECAST PERIOD WILL BEGIN WITH SURFACE HIGH PRESSURE
RIDGING INTO THE AREA FROM THE NORTH. THE UPPER LEVEL FLOW WILL BE
PRIMARILY ZONAL OVER THE GULF OF MEXICO AND SOUTHEASTERN CONUS.
TEMPERATURES WILL BEGIN THE EXTENDED PERIOD NEAR OR ABOVE NORMAL.
THE 500 MB PATTERN WILL FEATURE A RIDGE DEVELOPING OVER THE AREA
AS A TROUGH MOVES ONSHORE ON THE WEST COAST. AS THE SURFACE RIDGE
SLIDES EAST AND A LOW DEVELOPS IN THE HIGH PLAINS...SOUTHERLY FLOW
WILL DEVELOP AND START TO BRING TEMPERATURES EVEN WARMER. QUIET
WEATHER WILL CONTINUE WITH SOUTHERLY FLOW THROUGH WEDNESDAY.
RIDGING WILL STRENGTHEN AT 500 MB AND AS A STRONG COLD FRONT
DEVELOPS IN THE MISSISSIPPI VALLEY...TEMPERATURES WILL STAY WARM
WITH INCREASED HUMIDITY. INCREASED RAIN CHANCES BY DAY 7 WITH THE
APPROACH OF WHAT LOOKS TO BE A STRONG COLD FRONT WITH SIGNIFICANT
TROUGHING ACROSS THE CENTRAL STATES.

.AVIATION...
HIGH PRESSURE WILL MOVE OFF THE EAST COAST TODAY AND CONTINUE THE
EASTERLY FLOW ACROSS THE AREA. VFR CONDITIONS ARE EXPECTED TO
CONTINUE WITH MAINLY JUST BKN CLOUDS AROUND 5KFT. WINDS WILL
INCREASE AFTER 14-16Z AND BECOME SUSTAINED AT 12-15KTS WITH GUSTS
UP TO 25KTS THROUGH THE EARLY AFTERNOON.

&&

.MARINE...
WINDS HAVE DIMINISHED ACROSS THE NEAR SHORE WATERS AND TAMPA BAY
AND WILL LOWER SMALL CRAFT ADVISORY AND LEAVE EXERCISE CAUTION UP
THIS MORNING. THE BREEZY EASTERLY FLOW WILL PERSIST THROUGH
TONIGHT WITH MORE ADVISORY CRITERIA EXPECTED TO DEVELOP THIS
EVENING. THEN WINDS AND SEAS WILL DIMINISH SOME ON SATURDAY AS
THE FLOW BECOMES SOUTHEASTERLY WITH A SEA BREEZE DEVELOPING IN THE
AFTERNOON. WINDS WILL CONTINUE TO VEER AROUND TO THE SOUTH
SATURDAY NIGHT THEN BECOME NORTHERLY BEHIND THE FRONT DURING
SUNDAY AND SUNDAY NIGHT. HIGH PRESSURE WILL BUILD IN FROM THE
NORTH EARLY NEXT WEEK WITH A BREEZY NORTHEAST TO EAST FLOW
BECOMING ESTABLISHED ONCE AGAIN.

&&

.FIRE WEATHER...
RELATIVE HUMIDITY VALUES ARE EXPECTED TO DROP BELOW 35 PERCENT
THIS AFTERNOON ALONG WITH SUSTAINED TWENTY FOOT WINDS AROUND 15
MPH FROM THE TAMPA BAY AREA SOUTHWARD AND WILL ISSUE RED FLAG
WARNING FOR THESE AREAS. MOISTURE WILL GRADUALLY INCREASE ON
SATURDAY AND CLOUDS AND SHOWERS ARE EXPECTED TO BE AROUND ON
SUNDAY WITH NO FIRE WEATHER CONCERNS. MORE DRY AIR AND BREEZY
CONDITIONS WILL RETURN EARLY NEXT WEEK WITH RED FLAG WARNINGS A
GOOD POSSIBILITY.

&&

.PRELIMINARY POINT TEMPS/POPS...
TPA  81  61  80  62 /   5   5  10  20
FMY  82  58  83  61 /   5   5  10  10
GIF  79  57  80  61 /   5   5  10  20
SRQ  81  56  80  61 /   5   5  10  20
BKV  80  55  81  57 /   5   5  10  30
SPG  79  62  78  64 /   5   5  10  20

&&

.TBW WATCHES/WARNINGS/ADVISORIES...
FL...RED FLAG WARNING FROM NOON TODAY TO 5 PM EST THIS AFTERNOON FOR
     CHARLOTTE-DE SOTO-HARDEE-HILLSBOROUGH-LEE-MANATEE-PASCO-
     POLK-SARASOTA.

GULF WATERS...SMALL CRAFT ADVISORY UNTIL 10 AM EST THIS MORNING FOR
     BONITA BEACH TO ENGLEWOOD OUT 20 TO 60 NM-ENGLEWOOD TO TARPON
     SPRINGS OUT 20 TO 60 NM-TARPON SPRINGS TO SUWANNEE RIVER OUT
     20 TO 60 NM.

&&

SHORT TERM/MARINE/FIRE WEATHER...69/CLOSE
LONG TERM/AVIATION...35/JOHNSON