Lake Wind Advisory 10, NWS Melbourne, FL

EAST CENTRAL FLORIDA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MELBOURNE FL
942 PM EDT MON MAY 18 2009

.DISCUSSION...
...WET PATTERN CONTINUES INTO MIDWEEK...
...HAZARDOUS BOATING AND BEACH CONDITIONS AT THE ATLANTIC COAST AS
LOW PRESSURE SPINS UP SOUTH OF FLORIDA...

RECENT ANALYSIS CONFIRMS TIGHTENING OF PRESSURE GRADIENT NORTH OF
STALLED FRONTAL BOUNDARY ALONG THE FL EAST COAST. STOUT ONSHORE
WINDS FROM VOLUSIA COAST NORTHWARD ARE PUSHING PERSISTENT SHOWER
ACTIVITY WELL INLAND ALONG THE VOLUSIA/FLAGLER COASTS. OCCASIONAL
SHOWERS WILL BE ACCOMPANIED BY WIND GUSTS IN THE 30 TO 35 MPH RANGE
ALONG THE COASTAL AREAS WITH ACCUMULATING RAINS CONTINUING INTO THE
EARLY MORNING HOURS. ELSEWHERE SHOWERS ASCD WITH THE STALLED
BOUNDARY MAINLY OVER THE SOUTHERN PORTION OF THE AREA WILL BE
POSSIBLE OVERNIGHT WITH LESSER COVERAGE EXPECTED AWAY FROM THE
COAST. THE CURRENT FORECAST PKGS ARE IN GOOD SHAPE AND NO CHGS ARE
PLANNED.

*** PREV DISC BELOW ***

TONIGHT/TUE...FRONTAL BOUNDARY WILL REMAIN STALLED OVER THE AREA
TONIGHT INTO TOMORROW KEEPING A VERY MOIST AIRMASS ON PLACE. IN
ADDITION TO THIS...THE UPPER LEVEL TROUGH OVER THE AREA WILL BEGIN
TO FORM INTO A CUTOFF LOW PRESSURE SYSTEM WHICH WILL KEEP TEMPS COOL
ALOFT AND THE WEATHER PATTERN UNSETTLED. THEREFORE WILL KEEP LIKELY
POPS (60-70 PERCENT) OVER THE AREA. CLOUD COVER WILL LIMIT
INSTABILITY OVER THE AREA SO WILL ONLY MENTION A CHANCE FOR
THUNDERSTORMS. STRONGER STORMS WILL CONTINUE TO BE ABLE TO PRODUCE
LOCALIZED HEAVY RAINFALL WITH RAINFALL RATES UP TO ONE TO TWO INCHES
PER HOUR. TIGHTER PRESSURE GRADIENT OVER NORTHERN SECTIONS OF THE
CWA WILL KEEP WINDS ELEVATED OVERNIGHT UP TO 10 TO 15 MPH OUT OF THE
NORTHEAST. THESE WINDS COULD CONTINUE TO BECOME STRONGER INTO
TOMORROW DEPENDING ON DEVELOPMENT OF A LOW PRESSURE SYSTEM SOUTH OF
THE AREA...HOWEVER MODELS ARE CONTINUING TO HAVE A HARD TIME
RESOLVING THIS FEATURE SO WILL KEEP WINDS AS IS FOR NOW.

TUE NGT-WED NGT...CONTINUE TO FAVOR THE MORE WWD ECM/UKM SOLNS OVER
THE GFS (WHICH SEEMS TO OVERDEVELOP THE WEAK LOW JUST NORTH OF THE
ERN CUBA COAST) AND THE NAM (WHICH LOOKS TOO LOW WITH THE CTRL PRES
OVER FL. HENCE...EXPECT BEST PRES FALLS/SFC CYCLOGENESIS WILL OCCUR
CLOSER TO THE MID-UPR CUTOFF LOW CTR...WHERE VERTICAL ASCENT WILL BE
STRONGEST. SYSTEM WILL GRDLLY SPIN UP AND THEN BE SLOW TO DRIFT WWD
INTO THE GOMEX. TIGHTENING PGRAD COUPLED WITH HIGH PWAT VALUES INVOF
DECAYED/WASHED OUT FRONTAL BDRY WILL KEEP ECFL IN A VERY MOIST AND
UNSETTLED WX REGIME...WITH FAIRLY WDPRD COVRG OF RAINFALL THROUGH AT
LEAST WEDNESDAY NGT. BRISK EASTERLIES MAY GIVE A SQUALLY TYPE FEEL
TO THE WX AS SHRA BANDS EMBEDDED WITHIN WDSPRD STRATIFORM RAINFALL
REPEATEDLY MOVE ONSHORE.

THU-SUN...(PREV) FCST WILL HINGE LARGELY ON HOW THE ANTICIPATED LOW
PRESSURE SYSTEM DEVELOPS AND INTERACTS WITH THE FRONTAL TROF AND THE
SURROUNDING MOISTURE FIELD. GIVEN THE NUMBER OF ELEMENTS IN PLAY AND
THE FACT THE LOW IS STILL MORE OR LESS AN OPEN WAVE...WILL MAKE ONLY
MINOR ADJUSTMENTS TO THE PREVIOUS EXTENDED FCST. EXPECT TO GRADUALLY
TREND TWDA MORE DIURNAL-DRIVEN CONVECTIVE REGIME WITH POPS REMAINING
MORE TYPICAL OF LATE JUNE/EARLY JULY RATHER THAN MID-LATE MAY.

&&

.AVIATION...FRONTAL BOUNDARY OVER THE AREA WILL CONTINUE TO STIR UP
SHOWERS AND THUNDERSTORMS TONIGHT INTO TOMORROW. CONDITIONS WILL
REMAIN PREDOMINANTLY MVFR WITH TEMPO REDUCTIONS TO IFR IN ANY
STRONGER SHRA/TSRA ACTIVITY.

&&

.MARINE...STRONG PRESSURE GRADIENT EXISTS BEHIND THE FRONTAL
BOUNDARY WITH BUOY 41012 UP TO 20-25 KTS OUT OF THE NE AND EXPECTING
THIS WIND TO FILTER DOWN INTO THE NORTHERN WATERS SO WILL KEEP SCA
IN THIS AREA CONTINUING FOR THIS AFTERNOON INTO THE EVENING HOURS.
SCA CONDITIONS THEN WILL EXTEND SOUTHWARD OVER ALL OF THE WATERS
TONIGHT INTO TOMORROW AS ELEVATED E/NE WINDS BUILD SEAS TO HAZARDOUS
LEVELS.

HAZARDOUS BOATING CONDITIONS EXPECTED TO CONTINUE THRU THE WEEK AS A
HIGH PRESSURE RIDGE OVER THE MIDWEST MOVE INTO THE MID ATLC/MID
SOUTH REGION.  AS IT DOES...IT WILL PUSH A FRONTAL TROUGH FROM THE
FL PANHANDLE INTO THE CENTRAL PENINSULA BY DAYBREAK TUE.  TIGHT
PGRAD BETWEEN THE RIDGE AND THE TROUGH WILL GENERATE A FRESH TO
STRONG ERLY FLOW BY DAYBREAK WED WITH SEAS BUILDING TO 5-7FT
NEARSHORE...8-10FT OFFSHORE. LOW PRES PROGGED TO FORM SOUTH OF
FL WILL TIGHTEN PGRAD FURTHER INTO WED...WITH WINDS INCREASING TO
NEAR GALE FORCE AND SEAS BUILDING TO >12FT  OVER THE OFFSHORE WATERS
WED/WED NGT. HAVE HELD OFF ON ISSUING GALE WATCH FOR NOW...BUT COULD
EASILY SEE GALE CONDS REALIZED...DEPENDING UPON STRENGTH/POSN OF SFC
LOW PRES CTR. PREFER TO WAIT UNTIL LOW ACTUALLY STARTS TO GET
CRANKING BEFORE PULLING THE TRIGGER.

HAZARDOUS MARINE CONDS WILL SLOWLY ABATE ONCE LOW PULLS WWD AWAY FROM
FL...THOUGH SPEED AT WHICH IT DOES SO REMAINS IN QUESTION. PROBABLY
LOOKING AT NO SOONER THAN FRI BEFORE CONDS BECOME LESS DANGEROUS.

&&

.HYDROLOGY...FRONTAL BOUNDARY DROPPING INTO THE AREA AND STALLING
WILL INCREASE MOISTURE SUBSTANTIALLY TODAY-TUE...THEN A LOW PRESSURE
AREA MOVING UP FROM THE SOUTH TO SOUTHEAST SHOULD PROLONG THE WET
REGIME THROUGH MID-LATE WEEK. BASIN AREAL AVG RAINFALL ACCUMULATIONS
EXPECTED TO BE SEVERAL INCHES AREAWIDE...WHICH WOULD HELP REPLENISH
LOCAL LAKE LEVELS...RECHARGE THE AQUIFER...AND OF COURSE PROVIDE SOME
BADLY NEEDED RELIEF FROM THE WILDFIRE THREAT.

&&

.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...SMALL CRAFT ADVISORY UNTIL 10 PM EDT THURSDAY FOR COASTAL WATERS
     FROM FLAGLER BEACH TO VOLUSIA BREVARD COUNTY LINE OUT 20 NM-
     WATERS FROM FLAGLER BEACH TO VOLUSIA BREVARD COUNTY LINE 20
     TO 60 NM OFFSHORE.

     SMALL CRAFT ADVISORY FROM 8 AM TUESDAY TO 10 PM EDT THURSDAY FOR
     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 SEBASTIAN INLET TO
     JUPITER INLET 20 TO 60 NM OFFSHORE.

     SMALL CRAFT ADVISORY FROM 2 AM TUESDAY TO 10 PM EDT THURSDAY FOR
     WATERS FROM VOLUSIA BREVARD COUNTY LINE TO SEBASTIAN INLET
     20 TO 60 NM OFFSHORE.

&&

JP/ALM

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE MELBOURNE FL
911 PM EDT MON MAY 18 2009

AMZ550-552-555-570-572-575-FLZ041-044>047-053-054-058-059-064-141-
144-147-191200-
COASTAL WATERS FROM FLAGLER BEACH TO VOLUSIA BREVARD COUNTY LINE
OUT 20 NM-
COASTAL WATERS FROM VOLUSIA BREVARD COUNTY LINE TO SEBASTIAN
INLET OUT 20 NM-
COASTAL WATERS FROM SEBASTIAN INLET TO JUPITER INLET OUT 20 NM-
WATERS FROM FLAGLER BEACH TO VOLUSIA BREVARD COUNTY LINE 20 TO
60 NM OFFSHORE-
WATERS FROM VOLUSIA BREVARD COUNTY LINE TO SEBASTIAN INLET 20 TO
60 NM OFFSHORE-
WATERS FROM SEBASTIAN INLET TO JUPITER INLET 20 TO 60 NM OFFSHORE-
INLAND VOLUSIA-NORTHERN LAKE-ORANGE-SEMINOLE-SOUTHERN BREVARD-
OSCEOLA-INDIAN RIVER-OKEECHOBEE-ST. LUCIE-MARTIN-COASTAL VOLUSIA-
SOUTHERN LAKE-NORTHERN BREVARD-
911 PM EDT MON MAY 18 2009

THIS HAZARDOUS WEATHER OUTLOOK IS FOR EAST CENTRAL FLORIDA.

.DAY ONE...TONIGHT.

...THUNDERSTORM IMPACT...
WIDESPREAD SHOWERS AND THUNDERSTORMS THIS AFTERNOON AND EVENING
IN ADDITIONAL CLOUDY SKIES FROM THE EARLIER CONVECTION HAVE HELPED
TO STABILIZE THE ATMOSPHERE OVER CENTRAL FLORIDA. NONETHELESS...THE
INTERACTION OF A FRONTAL BOUNDARY OVER SOUTH FLORIDA AND A WEAK
AREA OF LOW PRESSURE OFFSHORE EASTERN FLORIDA WILL CONTINUE TO
BRING A THREAT OF ISOLATED STORMS EMBEDDED WITHIN THE STRATIFORM
RAIN. A FEW STORMS THAT MOVE ONSHORE THE IMMEDIATE COAST MAY BE
ABLE TO PRODUCE FREQUENT LIGHTNING STRIKES AND WIND GUSTS UP TO 40
MPH.

...FLOOD IMPACT...
RECORD RAINFALL AMOUNTS HAVE BEEN REPORTED MANY AREAS THIS
AFTERNOON WITH LIGHT TO MODERATE RAIN CONTINUING TO FALL THIS
EVENING AND OVERNIGHT. ANY HEAVIER SHOWERS OVERNIGHT WILL LEAD TO
EXCESSIVE RUNOFF IN AREAS THAT HAVE RECEIVED HEAVIER RAIN THIS
AFTERNOON...WITH LOCALIZED NUISANCE FLOODING ALONG AREA
ROADWAYS...POOR DRAINAGE AREAS...AN DIN LOW LYING SPOTS. THE
THREAT IS GREATEST ALONG THE COAST WITH HEAVIER SHOWERS MOVING ON
SHORE...AND ACROSS NORTHERN SECTION OF VOLUSIA AND LAKE COUNTIES
THAT HAVE SEEN HIGHER RAINFALL AMOUNTS.

...MARINE THUNDERSTORM GUST IMPACT...
SCATTERED STORMS WILL MOVE NORTHEASTWARD ACROSS THE WATERS OVERNIGHT...WITH
STRONGER STORMS CONTAINING WIND GUSTS AROUND 30 KNOTS.

...WIND AND SEA IMPACT...
THE PRESSURE GRADIENT WILL TIGHTEN OVER THE WATERS NORTH OF CAPE
CANAVERAL AS A WEAK AREA OF LOW PRESSURE FORMS TO THE EAST OF THE
CAPE. NORTH TO NORTHEAST WINDS WILL INCREASE OVER THESE REGION
OVERNIGHT...SO A SMALL CRAFT ADVISORY IS IN EFFECT FOR THESE AREAS.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY.
A LOW PRESSURE CENTER IS FORECAST TO DEVELOP SOUTH OF THE AREA BY
TUESDAY AND MOVE SLOWLY ACROSS SOUTH FLORIDA INTO THE GULF OF
MEXICO. INCREASING ONSHORE WINDS WILL LEAD TO HAZARDOUS BOATING
CONDITIONS THROUGH LATE WEEK. THE LOW PRESSURE SYSTEM WILL ALSO
KEEP RAIN CHANCES HIGH THROUGH AT LEAST MID WEEK...WITH A THREAT
FOR HEAVY RAINFALL.

.SPOTTER INFORMATION STATEMENT...

SPOTTERS ARE REQUESTED TO MONITOR THE WEATHER AND SELF ACTIVATE
IF NEEDED.

MOSES