Coastal Flood in Florida, September 21 to 30, 2015

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE KEY WEST FL
235 PM EDT MON SEP 21 2015

.DISCUSSION...
.CURRENTLY...
SKIES ARE PARTLY TO MOSTLY SUNNY ALONG WITH TEMPERATURES HOVERING IN
THE UPPER 80S ALONG THE ISLAND CHAIN. MEANWHILE...LOCAL RADARS ARE
DETECTING A FEW SHOWERS IN OUR COUNTY WARNING AREA...BUT SHOWERS ARE
SLOWLY INCREASING ON DADE AND MONROE COUNTIES. SURFACE WISE...A WEAK
PRESSURE PATTERN IS COVERING OUR REGION...RESULTING IN LIGHT AND
VARIABLE WINDS EXCEPT MOST EAST NEAR 5 KNOTS ON THE OUTER STRAITS BEYOND
40 NM SOUTH OF THE ISLAND CHAIN.

.SHORT TERM (TONIGHT THROUGH THURSDAY NIGHT)...A ROBUST AND
DEEP...MID AND AND UPPER LEVEL TROUGH OVER THE EAST CENTRAL UNITED
STATES WILL PLOW SOUTHEASTWARD INTO THE EASTERN GULF OF MEXICO ON
TUESDAY...BEFORE PINCHING OFF AND BECOMING NEARLY STATIONARY THROUGH
THURSDAY NIGHT. DESPITE THE CYCLONIC FLOW ALOFT...MODEL GUIDANCE
REMAIN CONSISTENT WITH SHOWING LITTLE IF ANY REFLECTION BELOW WITH
A LIGHT AND CHAOTIC FLOW BELOW 700 MB. FURTHERMORE...FORECAST
SOUNDINGS REVEAL MOISTURE ON THE INCREASE ABOVE 700 MB. REGARDLESS...WILL
RETAIN CHANCE POPS BEGINNING TUESDAY...BUT WILL REMAIN BELOW BOTH MAV/ECS
MOS GUIDANCE FOR NOW DUE TO NO EVIDENT LOW LEVEL TRIGGERING MECHANISM. WITH
ADDITIONAL CLOUD COVER AND SCATTERED RAINFALL...HIGH TEMPERATURES
WILL AVERAGE IN THE UPPER 80S WITH OVERNIGHT LOWS RANGING FROM THE
MID 70S TO LOWER 80S.

&&

.LONG TERM (FRIDAY THROUGH MONDAY)...THE AFOREMENTIONED MID AND UPPER
LEVEL TROUGH WILL LIFT NORTHWESTWARD...ALLOWING THE WESTERN ATLANTIC
RIDGE TO EMERGE OVER THE FLORIDA PENINSULA AND OUR COUNTY WARNING
AREA THROUGH SUNDAY. MEANWHILE...GLOBAL MODELS CONTINUE TO INDICATE
A DEEP TROPOSPHERIC TROUGH/LOW LIFTING NORTHWARD INTO OR ALONG THE
YUCATAN PENINSULA...AND INTO THE SOUTH CENTRAL GULF OF MEXICO ON
MONDAY. DUE TO PLENTY OF UNCERTAINTY...WILL KEEP CHANCE POPS THROUGH
THE PERIOD. OTHERWISE...HIGHS IN THE UPPER 80S WITH LOWS RANGING FROM
THE MID 70S TO LOWER 80S PENDING ON RAINFALL.

&&

.MARINE...
VARIABLE WINDS OF AROUND 5 KNOTS WILL TURN NORTHEAST TO EAST AT 5 TO
10 KNOTS TONIGHT...BEFORE AVERAGING NEAR 10 KNOTS FOR THE BALANCE OF
THIS WEEK.

&&

.AVIATION...
VFR CONDITIONS WILL PREVAIL AT BOTH THE KEY WEST AND
MARATHON TERMINALS THROUGH THIS EVENING. SURFACE WINDS WILL BE
VARIABLE NEAR 5 KNOTS FOR THE REMAINDER OF THE AFTERNOON...BECOMING
GENERALLY EASTERLY NEAR 5 KNOTS THIS EVENING.

&&

.CLIMATE...ON THIS DATE IN FLORIDA KEYS WEATHER HISTORY...IN
1948...A CATEGORY 3 HURRICANE MADE ITS INITIAL UNITED STATES
LANDFALL NEAR SUGARLOAF KEY. THE WIND SPEED AT BOCA CHICA REACHED
122 MILES PER HOUR...BEFORE THE ANEMOMETER WAS BLOWN AWAY. A 5 FOOT
STORM TIDE WAS OBSERVED AT TAVERNIER. 4.53 INCHES OF RAIN FELL IN
KEY WEST...SETTING THE DAILY RECORD FOR MAXIMUM RAINFALL MEASURED IN
KEY WEST ON SEPTEMBER 21ST...A RECORD WHICH STILL STANDS 67 YEARS
LATER. RAINFALL RECORDS AT KEY WEST DATE BACK TO 1871.

&&

.PRELIMINARY POINT TEMPS/POPS...
KEY WEST  81  89  81  89 / 20 30 30 30
MARATHON  81  91  81  91 / 20 30 30 30

&&

.KEY WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GM...NONE.
&&

PUBLIC/MARINE.........APA
AVIATION/NOWCASTS.....AD
DATA ACQUISITION......SC

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HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE KEY WEST FL
1045 AM EDT MON SEP 21 2015

FLZ076>078-GMZ031>035-042>044-052>055-072>075-221000-
MONROE UPPER KEYS-MONROE MIDDLE KEYS-MONROE LOWER KEYS-
FLORIDA BAY INCLUDING BLACKWATER SOUND, BUTTONWOOD SOUND, AND
BARNES SOUND-
BAYSIDE AND GULFSIDE FROM CRAIG KEY TO WEST END OF SEVEN MILE
BRIDGE-
GULF WATERS FROM EAST CAPE SABLE TO CHOKOLOSKEE 20 TO 60 NM OUT
AND BEYOND 5 FATHOMS-
GULF OF MEXICO INCLUDING DRY TORTUGAS AND REBECCA SHOAL CHANNEL-
GULF OF MEXICO FROM WEST END OF SEVEN MILE BRIDGE TO HALFMOON
SHOAL OUT TO 5 FATHOMS-
HAWK CHANNEL FROM OCEAN REEF TO CRAIG KEY OUT TO THE REEF-
HAWK CHANNEL FROM CRAIG KEY TO WEST END OF SEVEN MILE BRIDGE OUT
TO THE REEF-
HAWK CHANNEL FROM WEST END OF SEVEN MILE BRIDGE TO HALFMOON SHOAL
OUT TO THE REEF-
STRAITS OF FLORIDA FROM OCEAN REEF TO CRAIG KEY OUT 20 NM-
STRAITS OF FLORIDA FROM CRAIG KEY TO WEST END OF SEVEN MILE
BRIDGE OUT 20 NM-
STRAITS OF FLORIDA FROM WEST END OF SEVEN MILE BRIDGE TO SOUTH OF
HALFMOON SHOAL OUT 20 NM-
STRAITS OF FLORIDA FROM HALFMOON SHOAL TO 20 NM WEST OF DRY
TORTUGAS OUT 20 NM-
STRAITS OF FLORIDA FROM OCEAN REEF TO CRAIG KEY 20 TO 60 NM OUT-
STRAITS OF FLORIDA FROM CRAIG KEY TO WEST END OF SEVEN MILE
BRIDGE 20 TO 60 NM OUT-
STRAITS OF FLORIDA FROM WEST END OF SEVEN MILE BRIDGE TO SOUTH OF
HALFMOON SHOAL 20 TO 60 NM OUT-
STRAITS OF FLORIDA FROM HALFMOON SHOAL TO 20 NM WEST OF DRY
TORTUGAS 20 TO 60 NM OUT-
1045 AM EDT MON SEP 21 2015

THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE FLORIDA KEYS AND ADJACENT
COASTAL WATERS.

.DAY ONE...TODAY AND TONIGHT

NO HAZARDOUS WEATHER IS EXPECTED ALONG THE FLORIDA KEYS AND THE
ADJACENT COASTAL WATERS TODAY.

FOR LATE TONIGHTISOLATED THUNDERSTORMS ARE POSSIBLE ALONG THE
FLORIDA KEYS...AS WELL AS OVER NEARSHORE AND OFFSHORE WATERS
SURROUNDING THE ISLAND CHAIN. THE PRIMARY THUNDERSTORM
HAZARD WILL BE CLOUD TO SURFACE LIGHTNING STRIKES.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY

SCATTERED THUNDERSTORMS ARE POSSIBLE ALONG THE FLORIDA KEYS...AS
WELL AS OVER NEARSHORE AND OFFSHORE WATERS ADJACENT TO THE ISLAND
CHAIN TUESDAY THROUGH SUNDAY. THE PRIMARY THUNDERSTORM HAZARD WILL
BE CLOUD TO SURFACE LIGHTNING STRIKES.

A SMALL CRAFT ADVISORY MAY BE REQUIRED FOR THE COASTAL WATERS OF THE
FLORIDA STRAITS SUNDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT ANTICIPATED.

APA