Area Forecast Discussion
Issued by NWS Melbourne, FL

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS62 KMLB 310037
AFDMLB

- KMIA 302346
WRKSTF

ZCZC MIAWRKSTF 302344
TTAA00 KMIA DDHHMM

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MELBOURNE FL
835 PM EDT SUN AUG 30 2015

.DISCUSSION...

...HEAVY RAIN AND FLOODING THREAT CONTINUES THROUGH MONDAY...

OVERNIGHT UPDATE...THE DEEP MOIST SOUTHERLY FLOW BETWEEN A TROUGH OF
LOW PRESSURE COVERING THE ENTIRE EASTERN GULF OF MEXICO AND THE
SOUTHEAST TO SOUTH FLOW AROUND THE WESTERN PERIPHERY OF HIGH
PRESSURE IN THE ATLANTIC OFF THE SOUTHEAST U.S. AND FLORIDA WILL
CONTINUE TO SUPPORT NUMEROUS SHOWERS AND SCATTERED STORMS THIS
EVENING. THE RADAR MOSAIC LOOP WAS SHOWING A SLOW DECREASING TREND
IN THE COVERAGE OF SHOWERS AND STORMS BUT NOT ENOUGH TO LOWER POP
FOR THE FIRST FEW HOURS OF THE UPDATE. COVERAGE DOES DECREASE ENOUGH
AFTER MIDNIGHT ON MAINLAND FLORIDA AS THE ATMOSPHERE STABILIZES A
LITTLE TO LOWER THE COVERAGE. HOWEVER...OVER THE COASTAL WATERS WITH
THE GULF STREAM COVERING MORE THAN THAN HALF OF THE AREA THE
ATMOSPHERE WILL REMAIN UNSTABLE ENOUGH FOR NUMEROUS SHOWERS AND
ISOLATED STORMS.

OTHER THAN AMENDMENTS TO THE WINDS THE FORECAST REMAINS UNCHANGED.

PREVIOUS ZONES DISCUSSION

TONIGHT...LOW LEVEL FLOW WILL GRADUALLY VEER TO THE SOUTH AS
INVERTED TROUGH SHIFTS SLOWLY WESTWARD INTO THE GULF OF MEXICO.
THE VERY MOIST ATMOSPHERE WILL ALLOW FOR SCATTERED TO NUMEROUS
SHOWERS AND STORMS TO LINGER INTO EVENING AGAIN...THEN EXPECT
LOWERING CHANCES AFTER MIDNIGHT. LOCALIZED FLOODING OF POORLY
DRAINED AREAS WILL BE POSSIBLE WHERE SHOWERS/STORMS MOVE
REPEATEDLY OVER THE SAME AREA.

MON...MOIST SOUTHERLY FLOW WILL CONTINUE ON THE BACKSIDE OF LOW
LEVEL INVERTED TROUGH IN THE EASTERN GULF.  WINDS SPEEDS WILL BE
DECREASING THROUGH THE COLUMN...SO DO NOT EXPECT LOW LEVEL
CONVERGENCE TO BE AS STRONG AS SUNDAY...NOR UPPER LEVEL DIVERGENCE
TO BE NEARLY AS BIG A FACTOR EITHER. STILL WITH THE HIGH MOISTURE
IN PLACE...POPS WILL BE HIGH. THE LATEST POPS ARE CLOSE TO THE PREVIOUS
FORECAST NUMBERS...70 PERCENT...SO WILL NOT CHANGE. THE SOUTHERLY
WIND TRAJECTORY WILL LIKELY FOCUS STORMS MAINLY IN THE AFTERNOON.

TUE...THE LATEST GFS MODEL RUN SHOWS SLOW MOVING INVERTED TROUGH OUT
IN THE EASTERN GULF.  THE DEEP MOISTURE BAND ALONG IT IS FORECAST TO
SHIFT WEST OF OUR AREA AS THE MODEL ADVECTS SOME DRIER AIR IN FROM
THE EAST.  PLENTY OF LOW LEVEL MOISTURE WILL EXIST...SO EVEN THOUGH
THE GFS SHOWS POPS LOWERING TO 20-40 PERCENT...WILL GO ABOUT 20
PERCENT ABOVE GUIDANCE VALUES FOR NOW AND STAY SOMEWHAT CLOSE TO THE
PREVIOUS FORECAST.  STORM CHANCES SHOULD AGAIN BE FOCUSED MOSTLY
DURING THE AFTERNOON.

WED-SAT...(PREVIOUS DISCUSSION)

LINGERING TROUGHINESS OVER EXTREME NE GULF OF MEXICO AND N FL AND S
GA AND ASSOCIATED MOISTURE POOL DAMPENS AND ABSORBED. A GENERAL SE-S
LOW-LVL FLOW FOR THE FORECAST AREA WITH THE SFC RIDGE SITUATED TO
THE N. ENVIRONMENT LOOKING TO RETURN TO RELATIVE CLIMO.
&&

.AVIATION...

RADAR TRENDS SUGGESTING VCTS WITH VFR/MVFR CEILINGS/VISIBILITY KSFB-
KISM WEST TO KLEE THROUGH MIDNIGHT(31/04Z) THEN VCSH VFR TO 31/15Z.
31/15Z TO 01/00Z VCTS WITH TEMPO MVFR CEILINGS/VISIBILITY ALL SITES.

PREVIOUS AVIATION DISCUSSION

BANDS OF SHOWERS/STORMS OCCASIONALLY WITH IFR HAVE SHIFTED INLAND
FOR THE MOST PART EXCEPT POSSIBLY KTIX-KDAB. STILL EXPECT OCCASIONAL
MVFR IN SHOWERS KMLB-KSUA THROUGH SUNSET. LOW LEVEL WINDS VEERING TO
THE SOUTH OVERNIGHT SHOULD CONFINE STORMS TO THE ATLANTIC...BUT HIGH
MOISTURE MAY ALLOW FOR ISOLATED SHOWERS TO LINGER OVER LAND. ON
MON...IT WILL REMAIN MOIST BUT THE SOUTHERLY FLOW SHOULD RETURN THE
AREA TO MORE OF THE TYPICAL DIURNAL PATTERN WITH IFR SHOWERS/STORMS
DEVELOPING IN THE LATE MORNING AND EARLY AFTERNOON.

&&

.MARINE...

CURRENT-OVERNIGHT...BUOY REPORTS INDICATING SEAS HAVE BEEN 6 TO 7
FEET WITH WINDS AROUND 15 KNOTS SO FAR THIS EVENING. THE SWELL
COMPONENT OF AROUND 4 FEET WILL BE SLOW TO DIMINISH AND SHOULD KEEP
COMBINED SEAS IN THE 6 TO 7 FOOT RANGE OFFSHORE AND IN THE
NEARSHORE/GULF STREAM SOUTH OF SEBASTIAN INLET MOST OF THE NIGHT.
THE SMALL CRAFT ADVISORY SET TO EXPIRE AT 4AM.

PREVIOUS

TONIGHT-MON...THE PRESSURE GRADIENT IS FORECAST TO SLOWLY EASE AS
LOW PRESSURE TROUGH PUSHES AWAY INTO THE GULF OF MEXICO WHILE THE
ATLANTIC RIDGE NOSES BACK INTO THE FLORIDA PENINSULA.

WILL NEED TO KEEP SMALL CRAFT ADVISORY GOING THROUGH THIS EVENING
THOUGH...AS THE GFS KEEPS SURFACE AND BOUNDARY LAYER WINDS AROUND
20 KNOTS. WINDS ON MON LOOK SOUTH/SOUTHWEST 15 KNOTS OR LESS.

EXPECT PLENTY OF NIGHTTIME SHOWERS/STORMS OVER THE COASTAL
WATERS...WHICH SHOULD LINGER WELL INTO MON ESPECIALLY FROM THE
CAPE NORTH.

TUE-THU...(PREVIOUS DISCUSSION)
RIDGE OF SFC HIGH PRESSURE SITUATED TO THE N WILL SUPPORT SE-S
WINDS 10 KNOTS OR LESS AND SEAS 3 FT OR LESS (EXCEPT 3 TO 4 FT ON
TUE OFFSHORE). MORE TYPICAL LATE SUMMER BOATING CONDITIONS.

&&

.HYDROLOGY...

EVENT RAINFALL TOTALS OF AROUND TO 2 TO 4 INCHES ARE FORECAST ACROSS
EAST CENTRAL FLORIDA THROUGH MONDAY NIGHT WITH LOCALLY HIGHER
AMOUNTS OF 5 TO 6 INCHES POSSIBLE. VERO BEACH HAS ALREADY BROKEN
RAINFALL RECORD FOR THIS DATE WITH 2.58" SO FAR...OLD RECORD WAS
2.02" IN 1981.

A HYDROLOGIC (RIVER) STATEMENT (RVSMLB) WAS ISSUED FOR SHINGLE CREEK
AT CAMPBELL (SHIF1)...WHICH WENT ABOVE ACTION STAGE LATE AFTERNOON.
IF RAINFALL IS PERSISTENT ENOUGH OVER THE BASIN...THEN FLOOD STAGE
COULD BE REACHED IN THE EARLY WEEK.

&&

.PRELIMINARY POINT TEMPS/POPS...
DAB  75  88  74  90 /  60  70  30  50
MCO  75  89  75  91 /  60  70  30  60
MLB  76  89  77  90 /  60  70  30  40
VRB  74  89  75  90 /  70  70  30  40
LEE  76  89  76  91 /  60  70  30  60
SFB  75  89  76  92 /  60  70  30  60
ORL  75  89  76  92 /  60  70  30  60
FPR  75  90  74  91 /  70  70  30  40

&&

.MLB WATCHES/WARNINGS/ADVISORIES...
FL...FLOOD WATCH THROUGH MONDAY EVENING FOR COASTAL VOLUSIA COUNTY-
     INDIAN RIVER-INLAND VOLUSIA COUNTY-MARTIN-NORTHERN BREVARD
     COUNTY-NORTHERN LAKE COUNTY-OKEECHOBEE-ORANGE-OSCEOLA-
     SEMINOLE-SOUTHERN BREVARD COUNTY-SOUTHERN LAKE COUNTY-ST.
     LUCIE.

AM...SMALL CRAFT ADVISORY UNTIL 4 AM EDT MONDAY FOR SEBASTIAN INLET
     TO JUPITER INLET 0-20 NM-SEBASTIAN INLET TO JUPITER INLET
     20-60 NM-VOLUSIA-BREVARD COUNTY LINE TO SEBASTIAN INLET 20-
     60 NM-FLAGLER BEACH TO VOLUSIA-BREVARD COUNTY LINE 20-60 NM-

&&

$$

IMPACT WX...PENDERGRAST
HYDRO.......GLITTO
UPDATES.....WIMMER



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.