FXUS62 KMLB 110846
AFDMLB
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MELBOURNE FL
346 AM EST SAT FEB 11 2012
.DISCUSSION...
...BELOW FREEZING WIND CHILLS EXPECTED OVER MUCH OF THE AREA LATE
TONIGHT AND EARLY SUNDAY MORNING...
TODAY-TONIGHT...WATER VAPOR IMAGERY SHOWS BASE OF UPPER LEVEL TROUGH
THAT BROUGHT MUCH NEEDED RAINFALL TO EAST CENTRAL FLORIDA BEGINNING
TO ENTER THE PENINSULA. RAINFALL...AHEAD OF THE TROUGH AND
ASSOCIATED WITH A SURFACE LOW OFF THE ATLANTIC COAST...WILL COME TO
AN END AROUND SUNRISE WITH A FEW LINGERING SHOWERS OVER THE SOUTHERN
TREASURE COAST THROUGH MID MORNING. MID-UPPER CLOUDS WILL ERODE THIS
MORNING WITH FRONTAL PASSAGE...BUT LOW LEVEL CLOUD COVER WILL LINGER
THROUGH THE MID-LATE AFTERNOON HOURS BEFORE A POLAR HIGH BUILDS IN
ACROSS THE CENTRAL UNITED STATES AND PRODUCES ENOUGH SUBSIDENCE TO
CLEAR SKIES OUT.
A TIGHTENING PRESSURE GRADIENT...RESULTING FROM THE LOW PRESSURE
SYSTEM MOVING NORTHEAST OVER THE ATLANTIC AND CONTINENTAL POLAR HIGH
OVER THE CONTINENTAL UNITED STATES ENCROACHING UPON ONE
ANOTHER...WILL PRODUCE NORTHWEST WINDS OF 15-20 MPH WITH GUSTS OF UP
TO 25-30 MPH AT TIMES. WILL ISSUE LAKE WIND ADVISORY FOR ENTIRE AREA
BEGINNING MID MORNING AND LASTING THROUGH SUNSET.
COLD AIR ADVECTION WILL OCCUR THROUGHOUT THE DAY AS A RESULT OF
NORTHWESTERLY LOW-MID LEVEL FLOW. THIS WILL KEEP HIGH TEMPERATURES A
COUPLE OF DEGREES BELOW NORMAL WITH UPPER 60S TO LOWER 70S ACROSS
MUCH OF THE AREA...EXCEPT FOR MIDDLE 70S ALONG THE SOUTHERN TREASURE
COAST. COLD AIR ADVECTION WILL CONTINUE THROUGH SUNDAY
MORNING...ALLOWING OVERNIGHT LOWS TO DIP INTO THE MID-UPPER
30S...EXCEPT FOR NEAR 40 ADJACENT TO SHORE ALONG THE TREASURE COAST.
OUTLYING AREAS WILL SEE LOWER 30S. THE BIG STORY WILL BE WIND CHILLS
AS WINDS REMAIN ELEVATED OUT OF THE NORTHWEST AT 10-15 MPH WITH
GUSTS TO 20 MPH. WILL ISSUE A WIND CHILL ADVISORY WITH THIS PACKAGE
DUE TO THE PROLONGED WARMTH THAT HAS BEEN EXPERIENCED ACROSS THE
AREA.
SUN-MON...SURFACE HIGH WILL SLIDE ACROSS THE DEEP SOUTH ON SUNDAY
AND INTO THE ATLANTIC BY MONDAY WITH MID AND UPPER LEVEL FLOW
BECOMING MORE ZONAL IN THE WAKE OF THE DEPARTING EAST COAST TROUGH.
COLD AIR ADVECTION WILL CONTINUE ON SUNDAY AS WINDS SHIFT TO THE
N/NE AROUND 15MPH. MAX TEMPS WONT GET OUT OF THE 50S IN MOST
LOCATIONS...REMAINING IN THE LOW 50S ACROSS VOLUSIA AND LAKE
COUNTIES AND MID TO UPPER 50S FOR ALL BUT MARTIN AND SAINT LUCIE
COUNTY WHERE TEMPERATURES WILL JUST CREEP INTO THE LOW 60S. BREEZY
WINDS FOR MOST OF THE DAY WILL KEEP WIND CHILLS IN THE 30S AND 40S
FOR MOST OF THE DAY...LEADING TO A VERY RAW DAY ESPECIALLY IN LIGHT
OF THE RECENT STRING OF ABOVE NORMAL TEMPERATURES.
THOUGH THE TREND WILL BE FOR THE LOW LEVEL FLOW TO SHIFT MORE OUT OF
THE NE SUN NIGHT IN RESPONSE TO THE MOVEMENT OF THE RIDGE...MODELS
ARE INDICATING THAT SURFACE WINDS WILL DECOUPLE AND MAY BACK MORE
OUT OF THE N-NW...LEADING TO ONE MORE NIGHT OF COLD AIR ADVECTION
ACROSS THE AREA. WITH LIGHTER WINDS AND MOSTLY CLEAR
SKIES...TEMPERATURES FIRST THING MON MORNING MAY BE A FEW DEGREES
COOLER THAN SAT NIGHT...DROPPING INTO THE LOW 30S ACROSS
LAKE/VOLUSIA AND OKEECHOBEE COUNTIES AND MID-UPPER 30S ACROSS THE
ORLANDO METRO AND BREVARD AND THE TREASURE COAST WEST OF I-95. AREAS
OF EAST OF I-95 WILL BE A LITTLE TRICKY AS ANY ONSHORE COMPONENT OF
THE WIND WILL KEEP TEMPERATURES SEVERAL DEGREES WARMER...WILL GO
WITH GUIDANCE WHICH HAS UPPER 30S/LOW 40S FOR THE IMMEDIATE COAST.
WINDS WILL VEER TO THE EAST ON MONDAY EFFECTIVELY CUTTING OFF THE
COLD AIR ADVECTION AND ALLOWING TEMPERATURES TO REACH INTO THE 60S
WITH OVERNIGHT LOWS IN THE MID-UPPER 40S.
TUES-FRI...THE FORECAST REMAINS UNCERTAIN FOR TUESDAY ONWARDS AS THE
11/00Z GFS AND ECMWF HAVE CHANGED THEIR RESPECTIVE POSITIONS IN
REGARDS TO THE NEXT SYSTEM MOVING ACROSS THE DEEP SOUTH. WHILE THE
GFS NOW SHOWS A FRONTAL PASSAGE ON WEDNESDAY WHILE THE ECMWF WASHES
OUT THE FRONT ACROSS N FLORIDA...BOTH SHOW A VERY WEAK SYSTEM IN
WHAT BECOMES FAIR ZONAL UPPER LEVEL FLOW. GIVEN THE TRENDS OF THE
WINTER...SUSPECT THE TRUE ANSWER LIES CLOSER TO THE CURRENT ECMWF IN
KEEPING RAIN CHANCES OUT OF MOST OF EAST CENTRAL FLORIDA AND THE
WESTERN ATLANTIC RIDGE PREVAILING. WILL CONTINUE TO KEEP MENTIONABLE
POPS OUT OF THE FORECAST. WITH FLOW EXPECTED TO BE GENERALLY
E-SE...TEMPERATURES WILL CLIMB TO ABOVE NORMAL BY MID WEEK IN THE
UPPER 70S AND LOW 80S.
&&
.AVIATION...KEPT ALL SITES IN PREVAILING VFR THROUGH TONIGHT WITH
TEMPO MVFR THROUGH EARLY THIS MORNING AS CLOUDS AND RAIN PUSH EAST
AND EXIT EAST CENTRAL FLORIDA. WINDS WILL BEGIN TO INCREASE OUT OF
THE NORTHWEST AT 15-20 KNOTS WITH GUSTS TO AROUND 25 KNOTS SHORTLY
AFTER SUNRISE. EXPECT ALL TEMPO CEILINGS AND VISIBILITIES TO END
BY 12-13Z.
&&
.MARINE...
TODAY-TONIGHT...UNFAVORABLE BOATING CONDITIONS WILL CONTINUE TO
DETERIORATE THROUGH THE PERIOD AS AN INCREASING PRESSURE GRADIENT
CAUSES WINDS TO INCREASE OUT OF THE NORTHWEST AT 25-30 KNOTS BY
TONIGHT WITH OCCASIONAL GUSTS TO GALE FORCE. WILL ISSUE SMALL
CRAFT ADVISORY DURING THE EARLY AFTERNOON THROUGH TONIGHT AS SEAS
BUILD TO 7-9 FEET NEARSHORE AND 10-13 FEET OFFSHORE...AND INCLUDE
CAUTIONARY STATEMENT UNTIL THEN.
SUN-MON...STRONG NW WINDS WILL DIMINISH TO 15-20KTS AND BECOME N-NE
THROUGH THE DAY AS HIGH PRESSURE PUSHES OVER THE DEEP SOUTH AND
WEAKENS. HOWEVER...HAZARDOUS BOATING CONDITIONS WILL CONTINUE AS
WINDS VEER TO THE NE SUN NIGHT...RESULTING IN CHOPPY CONDITIONS DUE
TO THE OPPOSING DIRECTIONS OF THE PREVAILING SFC WIND AND OCEAN
CURRENT. SEAS 6-8FT NEARSHORE AND UP TO 12FT OFFSHORE EARLY
SUN...DECREASING TO 4-6FT NEARSHORE AND 6-8FT OFFSHORE SUN NIGHT.
WINDS WILL VEER TO THE EAST AND DIMINISH TO 10KTS BY MIDDAY MONDAY
AS THE SURFACE HIGH MOVES OFF THE SOUTHEASTERN SEABOARD. ADVISORY
LEVEL SEAS MAY LINGER OVER THE GULF STREAM THRU MIDDAY BUT SHOULD
DROP BELOW 6FT BY SUNSET.
TUE/WED...PREVAILING WINDS S-SE 10-15KTS ON TUES BECOMING MORE SW ON
WEDNESDAY AS THE HIGH BUILDS INTO THE ATLC. THERE IS SOME MODEL
DIFFERENCES AS TO WHETHER A WEAK SFC FRONT DIPS INTO THE NORTHERN
WATERS LATE ON WEDNESDAY WHICH WOULD BRING WINDS AROUND TO THE
NORTH...BUT FOR NOW WILL KEEP PREVAILING ONSHORE FLOW WITH SPEEDS
5KTS OR LESS. SEAS 2-3FT NEARSHORE AND 3-4FT OFFSHORE.
&&
.FIRE WEATHER...
COOLER AND DRIER AIR WILL FILTER INTO EAST CENTRAL FLORIDA TODAY AS
NORTHWEST WINDS INCREASE TO 15-20 MPH. TEMPERATURES LOOK TO REMAIN
COOL ENOUGH ALONG WITH LINGERING LOW LEVEL MOISTURE LATE ENOUGH INTO
THE DAY TO KEEP MINIMUM RELATIVE HUMIDITY VALUES ABOVE 35 PERCENT.
STRONG DRY AIR ADVECTION BEHIND THE COLD FRONT WILL DROP MIN RH
VALUES TO 20-25 PERCENT ACROSS THE INTERIOR SUN AFTN WITH 30-35
PERCENT ACROSS VOLUSIA COUNTY. GRADIENT WILL REMAIN TIGHT ENOUGH TO
SUPPORT 10-15KT SFC/BINDERY LAYER WINDS. BOTH DURATION AND INSTANTANEOUS
FIRE WEATHER CONDITIONS ANTICIPATED...A FIRE WEATHER WATCH REMAINS IN
EFFECT FOR ALL INTERIOR COUNTIES AS WELL AS COASTAL VOLUSIA.
THOUGH THE FLOW BECOMES ONSHORE ON MONDAY...WIND SPEEDS WILL
DIMINISH AND MODIFICATION OF THE AIRMASS OVER THE INTERIOR WILL BE
MINIMAL. RH VALUES ARE EXPECTED TO DIP INTO THE MID 20S ONCE AGAIN
MONDAY AFTERNOON NORTH AND WEST OF I-4. THE PREVAILING S-SE FLOW
THROUGH THE REMAINDER OF THE WEEK WILL KEEP RH VALUES ABOVE CRITICAL
LEVELS FROM TUES ONWARDS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 68 35 52 33 / 0 0 0 10
MCO 70 38 56 37 / 0 0 0 10
MLB 70 39 57 37 / 10 0 0 10
VRB 72 41 59 40 / 10 0 0 10
LEE 68 33 53 32 / 0 0 0 10
SFB 70 36 54 34 / 0 0 0 10
ORL 70 38 55 37 / 0 0 0 10
FPR 72 40 59 40 / 10 0 0 10
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...LAKE WIND ADVISORY FROM 10 AM THIS MORNING TO 6 PM EST THIS
EVENING FOR ALL OF EAST CENTRAL FLORIDA.
WIND CHILL ADVISORY FROM 4 AM TO 9 AM EST SUNDAY FOR ALL OF
EAST CENTRAL FLORIDA.
FIRE WEATHER WATCH FROM SUNDAY MORNING THROUGH SUNDAY AFTERNOON
FOR COASTAL VOLUSIA-INLAND VOLUSIA-NORTHERN LAKE-OKEECHOBEE-
ORANGE-OSCEOLA-SEMINOLE-SOUTHERN LAKE.
AM...SMALL CRAFT ADVISORY FROM 1 PM THIS AFTERNOON TO 7 PM EST SUNDAY
FOR COASTAL WATERS FROM FLAGLER BEACH TO VOLUSIA BREVARD
COUNTY LINE OUT 20 NM-COASTAL WATERS FROM SEBASTIAN INLET
TO JUPITER INLET OUT 20 NM-COASTAL WATERS FROM VOLUSIA
BREVARD COUNTY LINE TO SEBASTIAN INLET OUT 20 NM-WATERS
FROM FLAGLER BEACH TO VOLUSIA BREVARD COUNTY LINE 20 TO 60
NM OFFSHORE-WATERS FROM SEBASTIAN INLET TO JUPITER INLET 20
TO 60 NM OFFSHORE-WATERS FROM VOLUSIA BREVARD COUNTY LINE
TO SEBASTIAN INLET 20 TO 60 NM OFFSHORE.
&&
$$
SHORT TERM/AVIATION...GUSEMAN
LONG TERM....MOSES
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