Area Forecast Discussion
Issued by NWS Melbourne, FL

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000
FXUS62 KMLB 020831 AAA
AFDMLB

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE MELBOURNE FL
432 AM EDT THU JUL 2 2015

.DISCUSSION...
THE CURRENT PATTERN WITH BROADLY CYCLONIC FLOW OVER THE EASTERN
CONUS WL CONTINUE. W TO SW STEERING FLOW AROUND 15 TO 20 KT ALONG
WITH AMPLE MOISTURE AND SFC HEATING WL LEAD TO AFTERNOON DEVELOPMENT
OF SCATTERED LIGHTNING STORMS. A MODEST TO WEAK LL PRESSURE GRADIENT
WL LEAD TO DEVELOPMENT OF THE EAST COAST BREEZE BOUNDARY AND OTHER
LOCALIZED BOUNDARIES BY MID AFTERNOON. LOW TO MID RANGE SCT COVERAGE
CAN BE EXPECTED SOME WITH EARLY SHOWERS AND PERHAPS LATE MORNING
PCPN MOVING EWD FROM THE FL WEST COAST TO THE I-4 CORRIDOR WITH
AN INCREASE IN LIGHTNING STORMS ONCE BOUNDARIES INTERACT. THE MAIN
CONCERN WL BE FOR CONVECTIVE WIND GUSTS AND LIGHTNING. EVENING
STORMS WILL TRANSITION TO THE COAST AND OFFSHORE DURING THE
EVENING AND SHOULD END OVER LAND FROM AROUND 10 TO 11 PM WITH LOSS
OF HEATING.

INDEPENDENCE DAY WEEKEND...
TROFING PATTERN OVER THE ERN CONUS WILL PERSIST AS A POSITIVE PNA
PHASE SPANNING THE CONTINENT HAS A FIRM GRIP ON THE WX PATTERN IS
SHOWING NO SIGN OF BREAKING DOWN ANYTIME SOON: NRN BRANCH OF THE
H30-H20 JET IS RATHER WEAK WITH MAX WINDS LARGELY AOB 70KTS...MOST
OF WHICH IS POSITIONED WELL N OF THE CANADIAN BORDER...CLOSEST
100KT JET STREAK THAT COULD UPROOT THE DEEP RIDGE OVER THE WRN
CONUS IS CURRENTLY OVER THE WEST PAC AND NOT EXPECTED TO AFFECT
THE CONUS UNTIL EARLY NEXT WEEK. A FRONTAL TROF EXTENDING FROM THE
MID ATLC TO THE MIDWEST IS EMBEDDED WITHIN DEEP WRLY FLOW THAT IS
LARGELY PARALLEL TO ITS ORIENTATION. THE BNDRY WILL DRIFT INTO THE
MID SOUTH/CAROLINA COAST ON FRI...BUT WITHOUT ANY SOURCE OF STRONG
MERIDIONAL FLOW...IT WILL STALL AND GRADUALLY WASH OUT OVER THE
WEEKEND BEFORE IT CAN PUSH INTO THE DEEP SOUTH.

PERSISTENT TROFING ACRS THE ERN CONUS WILL KEEP THE ATLC RIDGE AXIS
FROM DRIFTING MUCH FURTHER N THAN THE CENTRAL FL PENINSULA THRU THE
UPCOMING WEEKEND. THIS WILL RESULT IN A DEEP BUT WEAK S/SWRLY FLOW
THRU THE COLUMN WITH H100-H50 MEAN WINDS AOB 10KTS...H50-H20 MEAN
WINDS 10-15KTS.

WHILE SUCH FLOW REGIMES TEND TO FAVOR THE E HALF OF THE FL PENINSULA
FOR DIURNAL CONVECTION...THE FLOW WILL BE FLOW WILL BE TOO LIGHT FOR
STORM MOTION TO EXCEED 10MPH...THUS COVERAGE WILL BE AOB 50PCT.
REGIONAL MOISTURE IS SUFFICIENT FOR SCT POPS WITH MEAN RH AOA 60PCT
THRU THE H100-H50 LYR. LOW/MID LVL CONVECTIVE INHIBITION WILL BE
WEAK AS THE TROFING PATTERN PREVENTS THE ATLC RIDGE AXIS FROM
STRENGTHENING. H70 TEMPS BTWN 7-8C AND H50 TEMPS ARND -9C WILL YIELD
MAX LAPSE RATES BTWN 6.5-7.0C/KM THRU THE LYR. RIDGE AXIS WILL BLOCK
OUT MOST MID LVL VORT LOBES WHILE H30-H20 WINDS AOB 20KTS WILL
PRODUCE WEAK UPR LVL DIVERGENCE AT BEST.

WILL GO WITH A 30-50 POP COVERAGE...HIGHEST ALONG AND N OF THE I-4
CORRIDOR...LOWEST TREASURE COAST AS WEAK SW FLOW WILL FOCUS THE LAKE
OKEECHOBEE SHADOW ACRS THAT REGION. TEMPS SLIGHTLY ABV AVG AS IS
COMMON IN SW FLOW...MAXES IN THE L/M90S...MINS L/M70S.

MON-WED...
CPC/MID RANGE GUIDANCE CONTINUES TO POSITIVE PNA PHASE INTO EARLY
NEXT WEEK BEFORE DAMPENING OUT THE ERN TROF BY MIDWEEK. THE ATLC
RIDGE AXIS WILL CONTINUE TO MEANDER ACRS THE CNTRL/SRN FL PENINSULA
WITH WEAK S/SWRLY FLOW PREVAILING THRU THE LOW/MID LYRS OF THE
COLUMN. WILL KEEP DAILY POPS IN THE 30-50PCT RANGE THRU THE DAYTIME
PDS...CHC/SLGT CHC THRU THE EVNGS. TEMPS CONSISTENT WITH MID FL
SUMMER...MAXES L/M90S AND MINS L/M70S.

&&

.AVIATION...
VFR CONDS AREAWIDE THROUGH AROUND 02/15Z. ISOLD SHRA/TS MOVING
INTO NRN LOCATIONS AND I-4 CORRIDOR NR ISM-MCO-LEE-SFB PRODUCING
BRIEFLY MVFR CONDS. FM 02/17-02/21Z INCRSG CVG OF SHRA/TS WITH
MVFR PRIMARY IN AFFECTED AREAS ALNG WITH ISOLD IFR CONDS PSBL IN
TS THROUGH 03/01Z. BECMG VFR AREA WIDE AFT 03/02Z.

&&

.MARINE...
HIGH PRESSURE RIDGE CENTERED OVER S FL WL BRING S/SW WINDS
NR 10 KT OR LESS WITH SEAS 2 TO 3 FT THROUGH THIS EVENING. AN
ONSHORE SEABREEZE EXPECTED AT THE IMMEDIATE COAST FROM AROUND 2 PM
THROUGH 8 PM WITH CONDITIONS POSSIBLY INTERRUPTED BY OFFSHORE
MOVING STORMS WITH GUSTY WINDS AND CHOPPY SEAS ASSOCIATED WITH
STORMS INTO EARLY EVENING MAINLY N OF SEBASTIAN INLET.

INDEPENDENCE DAY WEEKEND...
ATLC RIDGE AXIS WILL DRIFT ACRS THE CNTRL/SRN FL PENINSULA...
MAINTAINING A GENTLE TO MODERATE SRLY BREEZE OVER THE LCL CSTL
WATERS...BCMG SE NEAR THE COAST EACH AFTN WITH THE FORMATION OF THE
EAST COAST SEA BREEZE. SEAS GENERALLY 2-3FT...UP TO 4FT OVER THE
OFFSHORE LEG N OF SEBASTIAN INLET. PRIMARY MARINE THREAT WILL BE
AFTN/EVNG TSRAS MVG OFFSHORE THAT WILL BE CAPABLE OF GENERATING SFC
WIND GUSTS IN EXCESS OF 35KTS.

&&

.PRELIMINARY POINT TEMPS/POPS...
DAB  93  73  91  74 /  40  20  40  30
MCO  95  74  94  75 /  40  20  40  20
MLB  93  74  91  76 /  40  30  40  30
VRB  92  74  92  75 /  30  20  30  30
LEE  95  76  93  76 /  40  20  40  20
SFB  96  75  94  75 /  40  20  40  20
ORL  95  76  94  76 /  40  20  40  20
FPR  92  72  92  74 /  20  20  30  20

&&

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

&&

$$

SHORT TERM...PENDERGRAST
LONG TERM....BRAGAW



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