Area Forecast Discussion
Issued by NWS Melbourne, FL

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000
FXUS62 KMLB 010844
AFDMLB

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MELBOURNE FL
444 AM EDT TUE SEP 1 2015

.DISCUSSION...

TODAY...RAP ANALYSIS SHOWS IMPRESSIVE VORT CENTER OVER EASTERN
GULF LIFTING NORTH WELL OFFSHORE THE FL WEST COAST. THIS IS LIKELY
PART OF WHAT IS LEFT OF "ERIKA". OUR AREA WILL BE UNDER A LIGHT
SOUTH TO SOUTHWEST FLOW BETWEEN AN INVERTED TROUGH AXIS IN THE
EASTERN GULF AND A WEAK ATLC HIGH PRESSURE RIDGE NOSING IN ACROSS
SOUTH FL. GFS SHOWS SOME DRIER AIR LIFTING NORTH INTO THE AREA
TODAY AND BLENDED TPW SAT PRODUCT IS SHOWING THIS AS WELL. SO
EXPECT A SLOW START TO CONVECTION TODAY WITH A RAIN-FREE MORNING.
CONVECTION SHOULD INITIATE ALONG THE FL WEST COAST AND PUSH INTO
THE INTERIOR THIS AFTERNOON WHERE A COLLISION WITH THE EAST COAST
SEA BREEZE LATE IN THE DAY ROUGHLY ALONG OR TO THE EAST OF THE I4
CORRIDOR. SO THIS IS WHERE HIGHEST POPS ARE DRAWN (50 PERCENT)
WITH ONLY ISOLATED (20 PERCENT) POPS FOR THE TREASURE COAST.

TEMPS ALOFT ARE WARM...+10C AT 700 MB AND -6C AT 500 MB...AND FLOW
ALOFT IS WEAK SO STORM INTENSITY WILL BE LIMITED. CELL MOTION WILL
BE TOWARD THE NORTH OR NORTHEAST AT 15-20 MPH. THE HEAVIEST RAINS
SHOULD FALL NORTH AND WEST OF THE AREA ALONG THE AXIS OF HIGHEST
PRECIP WATER ACROSS NW AND N FL. NONETHELESS...LOCALLY HEAVY RAIN
WILL OCCUR LATE TODAY ESP WITH THE SEA BREEZE COLLISION ROUGHLY
OVER THE ORLANDO METRO AREA OR JUST TO THE EAST.

TONIGHT...WILL HOLD ONTO A CHANCE FOR LINGERING RAIN AND ISOLATED
STORMS ALONG THE VOLUSIA AND N BREVARD COAST THIS EVE. DO NOT SEE
ANY REASON TO KEEP RAIN CHANCES PAST 11PM.

WED-THU...
THE ATLC RIDGE REMAINS WELL STAKED NE OF THE BAHAMAS AND WILL BE
THE PRIMARY WX FEATURE FOR CENTRAL FL. T-WAVE OVER THE ERN GOMEX
WILL LIFT INTO THE DEEP SOUTH AS IT RIDES AROUND THE PERIPHERY OF
THE RIDGE. A SECOND TROF EXTENDING FROM THE CAROLINAS TO THE
CANADIAN MARITIMES WILL INTERACT WITH THE RIDGE TO MAINTAIN A DEEP
AND STEADY S/SW FLOW OVERHEAD WILL CONTINUE...A PATTERN THAT TENDS
TO FAVOR POINTS ALONG AND N OF THE I-4 CORRIDOR FOR DIURNAL
PRECIP.

WEAK DRY AIR ADVECTION WILL OCCUR OVER THE SE CWA AS THE E/SE FLOW
AROUND THE BASE OF THE ATLC RIDGE PULLS A BAND OF RELATIVELY DRY AIR
IN FROM THE BAHAMAS. DEEPER MOISTURE TO THE N AS THE T-WAVE WORKS
ITS WAY INTO THE DEEP SOUTH AND TRIES TO MERGE WITH THE EAST COAST
TROF. THIS WILL FURTHER FAVOR AREAS ALONG AND N OF THE I-4 CORRIDOR
FOR PRECIP...ESPECIALLY AS PWAT VALUES REMAIN BTWN 1.8"-2.0".

TROFFING OVER THE DEEP SOUTH WILL KEEP THE RIDGE AXIS SUPPRESSED
OVER THE SRN PENINSULA...RESULTING IN S/SWRLY FLOW THRU THE H100-H50
LYR ARND 10KTS. EAST COAST SEA BREEZE FORMATION BY EARLY AFTN S OF
THE CAPE BUT WITH SLOW INLAND PROGRESS...LATE AFTN FROM THE CAPE
NWD. INTERIOR COUNTIES FROM OSCEOLA NWD WILL HAVE HIGHEST COVERAGE.
LITTLE IN THE WAY OF DYNAMIC SUPPORT THE RIDGE BLOCKS OUT ANY SHORT
WAVE VORT ENERGY...CONVECTION SHOULD BURN OUT SHORTLY AFT SUNSET.

WILL GO WITH A 40-60PCT SE TO NW SPLIT ON WED...INCREASING TO
50-60PCT ON WED TO ACCOUNT FOR A SLIGHTLY STRONGER WRLY STEERING
COMPONENT THAT WILL DELAY THE FORMATION AND INLAND PENETRATION OF
THE SEA BREEZE. SRLY WINDS WILL KEEP TEMPS IN U80S/L90S...MIN TEMPS
IN THE M70S.

FRI-MON...
A WEAK TROF ALNG THE SERN SEABOARD WILL PRESS INTO CENTRAL FL OVER
THE WEEKEND. GFS HAS SHIFTED TO A MORE ORGANIZED TROF WITH NE FLOW
DVLPG IN ITS WAKE...ECMWF STILL WASHES IT OUT BEFORE IT PENETRATES
INTO THE CENTRAL PENINSULA. NOT SURPRISINGLY...THE GFS EXTENDED MOS
GUIDANCE IS QUITE A BIT DRIER THAT THE ECMWF AS THE NE FLOW ON THE
BACKSIDE OF THE TROF USHERS IN A DRY/STABLE SLUG OF CONTINENTAL AIR.

AM INCLINED TO LEAN TOWARD THE EURO AS THE H30-H20 JET HAS A STRONG
ZONAL COMPONENT AND IS WELL N OF THE U.S./CANADIAN BORDER. IT WOULD
REQUIRE A SUBSTANTIAL AMOUNT OF AMPLIFICATION TO SWING IT FAR ENOUGH
SOUTH TO PULL THE TROF INTO CENTRAL FL. WHILE THIS WILL HAPPEN OVER
THE WRN CONUS AS A 120KT JET STREAK DIGS ITS WAY DOWN THE PAC COAST...
THE ERN CONUS WILL ONLY SEE INCREASED RIDGING AS A RESULT OF THE
BUCKLING. WILL KEEP SCT DIURNAL POPS IN THE FCST WITH TEMPS NEAR
CLIMO AVG.

&&

.AVIATION...
MAINLY VFR. PATCHY IFR CIGS POSSIBLE THROUGH 13Z ESP NORTH
INTERIOR. SCATTERED TSRA FCST TO MOVE IN FROM THE FL WEST COAST
TOWARD LEE IN THE EARLY AFTN THEN COLLIDE WITH THE EAST COAST SEA
BREEZE AFT 20Z OVER THE NORTH INTERIOR (DAB- SFB- MCO) WHICH COULD
LINGER A LITTLE PAST 00Z ESP DAB-TIX.

&&

.MARINE...
TODAY...SFC TROUGH IN THE EASTERN GULF COMBINED WITH A WEAK ATLC
RIDGE AXIS BUILDING BACK ACROSS SOUTH FL WILL PRODUCE A SOUTH TO
SOUTHWEST FLOW AROUND 10 KNOTS THIS MORNING...TURNING ONSHORE
IN A SEA BREEZE THIS AFTN. PRECIP COVERAGE LOOKS QUITE LOW GIVEN
SOME DRIER AIR MOVING IN FROM THE SOUTH. A FEW STORMS MAY PUSH
OFFSHORE NORTH OF THE CAPE EARLY THIS EVENING. SEAS 2-3 FEET BUT
THIS IS A COMBINATION OF A 1-2 FT WIND WAVE AND A COUPLE OF SMALL
LONG PERIOD SWELL COMPONENTS.

WED-THU...FAVORABLE BOATING CONDITIONS THRU MIDWEEK AS THE ATLC
RIDGE MAINTAINS A LIGHT TO GENTLE S/SW BREEZE...BCMG E/SE NEAR
THE COAST IN THE AFTNS AS THE SEABREEZE DVLPS. SEAS AOB 2FT.

FRI-SAT...SFC/BNDRY LYR WINDS BCMG VRBL AS A WEAK TROF PRESSES
INTO THE STATE...N/NE IN THE WAKE OF THE TROF...S/SE AHEAD OF IT.
WEAK PGRAD OVERHEAD WILL KEEP WIND SPEEDS AOB 10KTS WITH
ACCOMPANYING SEAS AOB 2FT.

&&

.HYDROLOGY...
FLOOD WATCH WAS ALLOWED TO EXPIRE LAST NIGHT AS DEEPEST MOISTURE
AND UPPER SUPPORT HAVE LIFTED NORTH AND WEST OF THE AREA. SO WE
ARE BACK TO OUR TYPICAL SUMMERTIME DIURNAL PATTERN OF AFTERNOON
AND EARLY EVE STORMS DRIVEN BY SEA AND LAKE BREEZE BOUNDARIES. BUT
BECAUSE THE ANTECEDENT RAINFALL HAS SATURATED THE GROUND IN SOME
PLACES...ANY ADDITIONAL RAIN FROM SCATTERED STORMS WILL BE MORE
APT TO CREATE STANDING WATER AND AGGRAVATE ONGOING FLOODING
CONCERNS.

&&

.PRELIMINARY POINT TEMPS/POPS...
DAB  89  76  89  75 /  40  30  60  40
MCO  91  75  92  75 /  50  20  60  30
MLB  89  76  90  76 /  30  20  40  30
VRB  90  76  90  75 /  30  20  40  30
LEE  90  76  91  77 /  50  20  60  30
SFB  92  75  92  76 /  50  30  60  30
ORL  91  76  93  76 /  50  20  60  30
FPR  90  76  90  75 /  30  20  40  30

&&

.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.

&&

$$

SHORT TERM...KELLY
LONG TERM....BRAGAW



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