Area Forecast Discussion
Issued by NWS Melbourne, FL

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795
FXUS62 KMLB 130849
AFDMLB

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MELBOURNE FL
349 AM EST SAT FEB 13 2016

.DISCUSSION...

...POOR TO HAZARDOUS BOATING CONDITIONS THIS WEEKEND...

TODAY-TONIGHT...
LATEST ANALYSIS SHOWS A DRY COLD FRONT PUSHING INTO THE PANHANDLE...
A LITTLE SLOWER THAN ANTICIPATED. THE 00Z KJAX/KTAE RAOBS INDICATE
PWATS ONLY ARND 0.75"...WHILE LATEST SAT PICS SHOW A FEW CLOUD BANDS
DVLPG AHEAD OF THE FRONT IN TANDEM WITH A BAND OF H100-H85 DEWPOINT
DEPRESSIONS BTWN 3-5C OVER THE NRN PENINSULA. AHEAD OF THE FRONT...
HOWEVER...A DRY/STABLE AIRMASS REMAINS IN PLACE. THE 00Z RAOBS AT
KXMR/KTBW/KMFL MEASURED PWAT VALUES ARND 0.50"...WHILE RAP ANALYSIS
INDICATES H100-H85 DEWPOINT DEPRESSIONS BTWN 5-7C ALONG THE I-4
CORRIDOR...ARND 15C OVER LAKE OKEECHOBEE AND THE TREASURE COAST.

AS EXPECTED...THE APPROACHING FRONTAL TROF HAS ERODED THE H100-H70
RIDGE/ANTICYCLONE AXIS THAT WAS IN PLACE OVER THE FL PENINSULA ON
FRI. THE RIDGE HAS EFFECTIVELY SPLIT IN TWO WITH THE WRN HALF
RETROGRADING INTO THE WRN GOMEX...THE ERN HALF PUSHING WELL E OF THE
BAHAMA BANK TO MERGE WITH THE ATLC SUBTROPICAL RIDGE. THIS WILL
LEAVE THE FRONT WITH LITTLE IMPEDANCE TO SLOW ITS FORWARD MOTION...
ESPECIALLY GIVEN THE RAP40 INDICATES AVG H100-H70 FLOW BEHIND IT IS
NW AT 25-30KTS.

ANOTHER QUIET WX DAY IN STORE AS FRONTAL MOISTURE IS SIMPLY TOO LOW
TO SUPPORT THE FORMATION OF ANYTHING MORE THAN A LOW LVL CLOUD
DECK...MEAN RH VALUES THRU THE H100-H85 LYR ARE AOB 80PCT.
FURTHERMORE...RAOBS SHOW A LINGERING SUBSIDENCE INVERSION IN THE
H90-H80 LYR THAT WILL PANCAKE ANY CLOUD DECK BLO 5KFT.

TEMPS WILL BE A BIT ON THE COOL SIDE FROM BREVARD/OSCEOLA CO NWD
ONCE THE FRONT PUSHES THRU AS NWRLY FLOW DVLPS...KEEPING AFTN
READINGS IN THE L/M60S DESPITE NEAR FULL SUN. TREASURE COAST/LAKE
OKEECHOBEE AREAS WELL HAVE TIME TO WARM INTO THE L70S BEFORE THE
FROPA...BUT EVEN THESE WILL BE 3-5F BLO AVG. TIGHTENING PGRAD BEHIND
THE FRONT WILL ALLOW NRLY WINDS TO PERSIST OVERNIGHT...RESULTING IN
A COOL AIR ADVECTION PATTERN THAT WILL ALLOW MIN TEMPS TO FALL INTO
THE L/M40S W OF I-95. MARINE INFLUENCE WILL KEEP COASTAL TEMPS A FEW
DEGS WARMER...GENERALLY U40S/L50S.


SUNDAY...
A HIGH PRESSURE RIDGE ALONG THE EASTERN SEABOARD WILL SHIFT
OFFSHORE. AN EARLY MORNING COASTAL TROUGH WILL EXIST THEN
DISSIPATE...GIVING WAY TO AN EASTERLY WIND FLOW IN THE AFTERNOON.
THE AIR MASS WILL INITIALLY BE VERY DRY SO COASTAL RAIN CHANCES
LOOK TO BE 10-15 PERCENT. WILL LEAVE SMALL POPS ALONG THE IMMEDIATE
COAST THROUGH SUNDAY NIGHT. FORECAST SOUNDINGS ARE STILL SUPPORTIVE
OF STRATOCUMULUS SPREADING INLAND FROM THE ATLANTIC. SO DESPITE
THE MORE MILD EAST WIND FLOW...THIS CLOUDINESS SHOULD KEEP DAYTIME
HIGHS A LITTLE BELOW THOSE FROM TODAY...MAINLY MID 60S NORTH AND
UPPER 60S SOUTH. ONSHORE LOW LEVEL WINDS WILL KEEP OVERNIGHT LOWS
MORE MILD...LOWER 50S NORTH INTERIOR AND UPPER 50S SOUTH COAST.

MON INTO EARLY TUE...
THIS PERIOD IS THE MAIN ITEM OF INTEREST FOR THE UPCOMING WEEK. A
SHORTWAVE TROUGH IS FORECAST TO MOVE ACROSS THE SOUTHERN STATES
AND SPIN UP A SURFACE LOW. THE 00Z GFS SHOWS A WEAKER SYSTEM FARTHER
NORTH THAN 24 HOURS AGO. HENCE THE LOCAL LOW LEVEL WIND FIELDS ARE
FORECAST TO BE WEAKER. PRECIPITABLE WATER IS STILL SHOWN TO ONLY
RECOVER TO ABOUT 1.3 INCHES WITH SURFACE DEW POINTS IN THE UPPER
50S TO LOWER 60S. MOS POPS HAVE BACKED OFF TO 30-40 PERCENT FOR
MON NIGHT. THE ECMWF ALSO SHOWS A WEAKER SYSTEM BUT THE POP VALUES
ARE A LOT HIGHER THAN THE GFS.

DO NOT WANT TO MAKE SIGNIFICANT CHANGES TO THE FORECAST JUST YET
AS THE SUBTROPICAL JET CORE WILL BE NEARBY AND TEMPS ALOFT WILL
BE QUITE COLD...SO EXPECT THAT THERE COULD BE ENOUGH SUPPORT FOR
CONVECTION OVER THE GULF OF MEXICO TO SPREAD WELL INLAND. HAVE
TRIMMED POPS BACK TO 50 PERCENT FOR MON NIGHT BUT KEPT SLIGHT
CHANCE FOR THUNDER. RECENT WEAKER MODEL SOLUTIONS FOR THIS SYSTEM
SUGGEST SOME SHOWER CHANCES MAY LINGER INTO TUE.

REST OF WEEK...
COLD FRONT IS FORECAST TO PUSH EAST OF THE AREA TUE OR TUE NIGHT...
BRINGING DRYING AND WEAK COLD AIR ADVECTION. A SURFACE HIGH
PRESSURE RIDGE WILL THEN BUILD FROM THE MIDWEST TO OFF THE
ATLANTIC SEABOARD BY SAT...WITH A RIDGE AXIS SETTLING INTO THE
LOCAL AREA. TEMPS LOOK CLOSE TO NORMAL. LATE WEEK ONSHORE FLOW
SHOULD PUSH A FEW SHOWERS TOWARDS THE COAST...BUT POPS ARE TOO LOW
TO MENTION. OTHERWISE IT LOOKS DRY.

&&

.AVIATION...THRU 14/12Z
SFC WINDS: THRU 13/12Z...W/SW 4-8KTS. BTWN 13/12Z-13/15Z BCMG N/NW
8-12KTS. BTWN 13/15Z-13/23Z...N/NW 12-15KTS OCNL G18-22KTS. BTWN
13/23Z-14/02Z...BCMG N 4-7KTS.

VSBY/WX/CIGS: VFR ALL SITES.

&&

.MARINE...
TODAY-TONIGHT...POOR BOATING CONDITIONS AS A DRY COLD FRONT PUSHES
THRU THE LCL ATLC WATERS. A MODERATE TO FRESH WRLY BREEZE THRU
DAYBREAK WILL VEER TO N/NW BY MIDDAY AS THE FRONT PUSHES THRU. ROUGH
SEAS AS WINDS MAKE THE SHIFT FROM AN OFFSHORE COMPONENT TO A NRLY
COMPONENT THAT WILL BLOW OPPOSITE TO THE GULF STREAM CURRENT.
PREVAILING WAVE HEIGHTS INCREASING FROM 2-4FT TO 4-6FT NEARSHORE...
AND FROM 4-6FT TO 5-7FT OFFSHORE. STEEP WAVES WITH DOMINANT PDS BTWN
5-7SEC. CURRENT ADVISORY/CAUTION ORIENTATION LOOKS FINE FOR NOW...
BUT MAY NEED TO EXPAND THE ADVISORY TO INCLUDE NEARSHORE TREASURE
COAST WATERS BY LATE AFTN DUE TO THE GULF STREAM`S CLOSER PROXIMITY
TO THE COAST.

SUN-MON...BREEZY NORTHEAST/EAST WINDS SUN WILL VEER TO SOUTHEAST
ON MON. THIS WILL KEEP CONDITIONS POOR FOR SMALL CRAFT OPERATION.

MON NIGHT-WED...BREEZY SOUTH FLOW IS INDICATED FOR MON NIGHT. THIS
WILL TRANSPORT MOISTURE NORTHWARD AND BRING A CHANCE OF SHOWERS
AND A SLIGHT CHANCE FOR STORMS. MODELS DIFFER A BIT ON THE TUE-
WED WINDS BUT OVERALL THE TREND IS FOR A WEAKER FRONTAL PASSAGE.

&&

.PRELIMINARY POINT TEMPS/POPS...
DAB  60  45  63  54 /   0   0  20  20
MCO  68  44  67  54 /   0   0  10  10
MLB  67  50  65  58 /   0   0  20  20
VRB  69  51  68  58 /   0   0  20  20
LEE  65  41  66  52 /   0   0  10  10
SFB  65  43  66  53 /   0   0  10  10
ORL  67  44  66  53 /   0   0  10  10
FPR  69  52  68  58 /   0   0  20  20

&&

.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...SMALL CRAFT ADVISORY UNTIL 4 AM EST SUNDAY FOR SEBASTIAN INLET
     TO JUPITER INLET 20-60 NM.

     SMALL CRAFT ADVISORY UNTIL 4 AM EST SUNDAY FOR FLAGLER BEACH TO
     VOLUSIA-BREVARD COUNTY LINE 20-60 NM-VOLUSIA-BREVARD COUNTY
     LINE TO SEBASTIAN INLET 20-60 NM.

&&

$$

SHORT TERM...BRAGAW
LONG TERM....LASCODY



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