FXUS62 KMLB 250926
AFDMLB
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MELBOURNE FL
425 AM EST WED NOV 25 2009
...WIDESPREAD RAIN TODAY WITH EMBEDDED SCATTERED THUNDERSTORMS --
HEAVY RAINFALL AND A FEW STRONG TO SEVERE STORMS POSSIBLE...
...MUCH DRIER AND COOLER AIR MASS ARRIVES THANKSGIVING DAY...
.DISCUSSION...
WARM FRONT HAS LIFTED TO JUST NORTH OF EC FL EARLY THIS MORNING.
SHRA/TSRA MAINLY OCCURRING NEAR AND NORTH OF THE BOUNDARY TO THE
NORTH...AND A CLUSTER OF TSRA IS MOVING OVER EXTREME S FL. EC FL
RAIN FREE WITH ONLY SOME PATCHY FOG AT THE PRESENT TIME.
TODAY/TONIGHT...THE SETUP IS UNFOLDING FOR AN ACTIVE WEATHER DAY IN
EC FL. WATER VAPOR IMAGES/RUC ANALYSIS SHOW A POTENT SHORTWAVE AND
SPEED MAX OVER THE GULF WITH INCREASING DIFFLUENCE ALOFT OVER THE
PENINSULA. GFS HAS MOVED FURTHER SOUTH WITH SURFACE LOW DEVELOPMENT
VERSUS EARLIER RUNS AND NAM NOT AS STRONG WITH SURFACE FEATURE BUT
STILL DEPICTS A TROF/SHEAR ZONE THAT WILL MOVE OVER EC FL. MAIN
CONCERNS WILL BE FOR SOME PERSISTENT/HEAVY DOWNPOURS WITH DEEP
MOISTURE OVER THE AREA AND THE SURFACE BOUNDARY HELPING PROVIDE
FOCUS...ALSO THE POTENTIAL EXISTS FOR A FEW ROTATING STORMS GIVEN
THE DYNAMICS ALOFT AND AREA OF (WEAK) ENHANCED SHEAR IN THE LOWER
LEVELS...ESP NEAR AND SOUTH OF THE SURFACE BOUNDARY. WILL DELINEATE
SPECIFIC THREAT AREAS A BIT MORE IN HWO/GHWO. HAVE CATEGORICAL POPS
IN FOR DAYTIME AND STAYED FAIRLY PESSIMISTIC INTO TONIGHT WITH SCT
N/LIKELY SOUTH. MAXES RANGE FROM THE MID 70S NORTH TO NEAR 80 SOUTH.
THU/FRI...A STORM SYSTEM OVER THE MIDWEST/GREAT LAKES WILL COMBINE
WITH A DLM RIDGE OVER THE BAHAMAS/GREATER ANTILLES TO GENERATE A
STRONG WRLY CONFLUENT FLOW ACROSS THE FL PENINSULA THRU FRI. THE
ANTICIPATED GOMEX STORM SYSTEM HAS YET TO FORM DESPITE THE PRESENCE
OF A 90KT H25 JET AND A RESPECTABLE H50 VORT MAX. ONCE IT DOES
FORM... HOWEVER...THE STRONG CONFLUENCE WILL KEEP IT ELONGATED...
PREVENTING IT FROM BECOMING WELL ORGANIZED AS IT CROSSES FL.
FURTHERMORE... THE WRLY FLOW WILL PUSH A VERY DRY AIRMASS FROM THE
SRN PLAINS/LWR MS VALLEY INTO FL ON THU...REDUCING THE CHANCES FOR
ADDITIONAL PRECIP.
LINGERING MOISTURE ASSOCD WITH THE APPROACHING COLD FRONT MAY ALLOW
ISOLD/SCT SHRAS TO CONTINUE INTO THU AFTN...BUT IMPACT WILL BE
MINIMAL WITH QPF AMOUNTS BLO 0.10". CLOUD COVER WILL DIMINISH THRU
THE DAY. HOWEVER...WITH SFC/LOW LVL WINDS SHIFTING TO THE NW BEHIND
THE FRONT...COOL AIR ADVECTION WILL OFFSET SFC HEATING...KEEPING MAX
TEMPS NEAR OR SLIGHTLY BLO CLIMO (L/M70S).
AS THE TROF AXIS FROM THE NRN TIER STORM SYSTEM CROSSES FL FRI
NIGHT...COLD AIR ADVECTION WILL BEGIN IN EARNEST...DROPPING FRI MIN
TEMPS A SOLID 10-15F DEG FROM THU MORNING MINS. EXPECT L/M40S N OF
THE I-4 CORRIDOR...AND L/M50S ALONG THE SPACE/TREASURE COASTS. THE
COLD AIR ADVECTION WILL CONTINUE THRU FRI...KEEPING MAX TEMPS ~10F
BLO CLIMO (M/U60S) DESPITE FULL SUN.
SAT/SUN...THE POST-FRONTAL H100-H85 RIDGE WILL PUSH ACROSS THE DEEP
S/GOMEX REGION THRU THE WEEKEND...MAINTAINING A COOL/DRY N/NWRLY
FLOW AND BLO CLIMO TEMPS ACROSS THE FL PENINSULA THRU SAT NIGHT. AS
THE RIDGE PUSHES OFF THE ERN SEABOARD ON SUN...WINDS WILL VEER
ONSHORE AND PUSH OCEAN MODIFIED AIR BACK ACROSS THE STATE...ALLOWING
TEMPS TO RECOVER BACK TO CLIMO NORMS.
MON/TUE...MID RANGE MODELS ARE DEVELOPING A STORM SYSTEM OVER THE
NATION'S MIDSECTION FROM A SHORT WAVE TROF CURRENTLY OVER THE NE
PAC. THE SOLUTION SEEMS REASONABLE GIVE THIS SYSTEM WILL HAVE THE
SUPPORT OF TWO STRONG H25 JET MAXES...ONE +140KT N OF HAWAII AND ONE
+180KT SOUTH OF THE ALEUTIANS. BOTH ECMWF/GFS MODES INDICATE THE
SYSTEM WILL CUTOFF TOWARD THE END OF THE FCST PD...BUT ALSO INDICATE
A STRONG BLOCKING RIDGE DEVELOPING OVER THE WRN ATLC. SUCH A WX
PATTERN WOULD INDICATE A SLOW MOVING COLD FRONT THRU THE DEEP SOUTH
WITH AN EXTENDED PD OF RAIN.
&&
.AVIATION...AREAS MVFR/LCL IFR DUE TO LOW STRATUS/FOG THROUGH AROUND
14Z. CIGS MAY HOVER NEAR MVFR DURING DAYTIME HOURS WITH TEMPO
REDUCTIONS MAINLY RESULTING FROM NMRS SHRA/SCT TSRA AFT 14Z.
&&
.MARINE...LOCAL WIND DIRECTIONS SHIFTING AS SURFACE BOUNDARY DRIFTS
BACK OVER THE WATERS FROM N FL. ADDED IN A CAUTIONARY HEADLINE FOR
LATE IN THE DAY FOR WINDS PICKING UP OVER THE OFFSHORE LEGS. WILL
NEED TO MONITOR IF ANY OF THESE AREAS WILL NEED AN SCA BY LATER
TODAY/TONIGHT. SHRA/TSRA OVER WATERS WILL BECOME WIDESPREAD WITH
POTENTIAL FOR A FEW WATERSPOUTS...ESP NEAR THE SURFACE BOUNDARY.
THU/SUN...COLD FRONT WILL PUSH THRU THE FL PENINSULA BY THU
AFTN...WITH WINDS BCMG NW AREAWIDE. WINDS WILL FRESHEN OUT OF THE
NW THU NIGHT AS A STRONG HIGH PRESSURE RIDGE BEGINS TO BUILD EAST
FROM THE SRN PLAINS. ANTICIPATE SCA CONDITIONS WILL PREVAIL BY
DAYBREAK FRI...CONTG INTO FRI NIGHT. CONDITIONS WILL IMPROVE ON SAT
AS THE CENTER OF THE RIDGE PUSHES ACROSS THE STATE...ALLOWING
WINDS/SEAS TO DIMINISH. . TREND WILL CONT INTO SUN THE RIDGE PUSHES
OFF THE SERN SEABOARD... ALLOWING WINDS TO SHIFT TO THE NE.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 74 59 72 45 / 90 40 30 0
MCO 77 59 73 48 / 90 50 30 0
MLB 77 64 75 49 / 90 60 30 0
VRB 79 64 77 51 / 90 60 30 0
LEE 75 57 72 45 / 90 40 10 0
SFB 77 59 73 46 / 90 50 20 0
ORL 77 60 73 48 / 90 50 20 0
FPR 79 63 77 51 / 90 70 30 10
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&
$$
SHORT TERM/AVIATION...GLITTO
LONG TERM....BRAGAW
