Areal Flood Advisory 7, NWS Key West, FL

AREA FORECAST DISCUSSION FOR THE FLORIDA KEYS
NATIONAL WEATHER SERVICE KEY WEST FL
1019 PM EDT TUE MAY 15 2012

.DISCUSSION...

CURRENTLY...DUE TO KBYX RADAR OUTAGE...KAMX RADAR SHOWS THE KEY WEST
CWA IS MOSTLY CLEAR OF PRECIP RETURNS. A FEW SHOWERS HAVE DEVELOPED
RECENTLY OFF OF THE UPPER KEYS AND NORTH OF THE LOWER KEYS...BUT IN
GENERAL...MOST RADAR RETURNS ARE CURRENTLY LIGHT RAIN OR NON-
METEOROLOGICAL OVER THE KEYS COASTAL WATERS. EVENING SOUNDING AT KKEY
SHOWS CONSIDERABLY UNSTABLE CONDITIONS AND ABUNDANT MOISTURE THROUGH
THE DEPTH OF THE PROFILE. THERE DOES NOT SEEM TO BE ANY LOCAL SOURCE
OF TRIGGER IN THE REGION THAT WAS ABLE TO ENCOURAGE SHOWER OR
THUNDERSTORM DEVELOPMENT. HOWEVER...AND WITH A PERSISTENT MID TO UPPER
LEVEL CLOUD DECK...DAYTIME LANDMASS HEATING WAS MUTED OVER THE ISLAND
CHAIN. THE WIND PROFILE HAS LARGELY SHIFTED TO SOUTH SOUTHWEST NEAR
10 KNOTS THROUGH 700 MB. ABOVE THAT...WINDS UNIFORMLY INCREASED ABOVE
500 MB...LARGELY FROM A ZONAL DIRECTION. THIS CONFIRMS THE PRESENCE
OF A SEASONALLY UNCHARACTERISTIC UPPER LEVEL JET AROUND THE CENTRAL
GULF OF MEXICO WITH A MODEL PROGGED 100 KNOT CORE BEYOND 400 NM TO
THE WEST NORTHWEST OF KEY WEST. ALL THE INGREDIENTS ARE IN PLACE FOR
SIGNIFICANT SHOWER OR THUNDERSTORM TO OCCUR...BUT CONDITIONS SHOULD
LARGELY REMAIN QUIET FOR THE NIGHT DUE TO THE AFOREMENTIONED LACK OF
REGIONAL TRIGGERS FOR CONVECTIVE ACTIVITY.

SHORT TERM...WITH A MOIST ATMOSPHERE IN PLACE...SIGNIFICANT CLOUD
COVER IS EXPECTED THROUGH THE OVERNIGHT AND WEDNESDAY TIME PERIODS.
WINDS HAVE LARGELY WANED ACROSS THE REGION TO NEAR 5 KNOTS. LIGHT AND
VARIABLE WINDS SHOULD PERSIST THROUGH THE OVERNIGHT TIME PERIOD.
MORE WIDESPREAD NOCTURNAL SHOWER OR THUNDERSTORM ACTIVITY IS POSSIBLE
OVERNIGHT BUT NEAR CLIMO POPS OF 30 PERCENT THROUGH TONIGHT AND
TOMORROW WILL SERVE WELL. THESE POPS THEN RAMP UP TO 50 PERCENT
THROUGH EARLY FRIDAY AS A SERIES OF LOW TO MIDLEVEL SHORT WAVES WILL
MOVE THROUGH THE REGION...PROVIDING A POSSIBLE FOCUS FOR ORGANIZED
SHOWER AND THUNDERSTORM DEVELOPMENT. IT WILL BE A SAFE BET THAT MOST
PORTIONS OF THE KEYS WILL SEE SOME RAIN BETWEEN NOW AND EARLY FRIDAY.
WITH A SIGNIFICANT JET IN THE MID AND UPPER LEVELS... STRONG
THUNDERSTORMS ARE POSSIBLE. NO CHANGES EXPECTED THROUGH THE TIME
PERIOD FOR THE PUBLIC WEATHER FORECASTS... MOST FORECAST PARAMETERS
WELL ON TRACK.

&&

.MARINE... WINDS HAVE LARGELY WANED AROUND THE REGION... VERY FEW
CHANGES PLANNED FOR THE FORECAST PACKAGE AS MOST SURFACE WINDS SHOULD
GO LIGHT AND VARIABLE OVERNIGHT...AND LARGELY REMAIN LIGHT OUT OF THE
SOUTH TO SOUTHEAST THROUGH THE NEXT FEW DAYS. EXTERNAL SWELLS ARE NOT
EXPECTED TO IMPACT THE REGION. MARINERS SHOULD REMAIN APPRISED OF
LOCAL SHOWER AND THUNDERSTORM ACTIVITY HOWEVER...AS SIGNIFICANT WIND
GUSTS MAY BE CREATED IN THE AREA OF THE STRONGEST THUNDERSTORMS.

&&

.AVIATION...
BRIEF...MVFR CEILINGS ARE LIKELY AT EYW AND MTH TONIGHT. THESE
CEILINGS SHOULD BE MOST FREQUENT BETWEEN MIDNIGHT AND 400 AM.
OUTSIDE OF THIS TIME PERIOD...ANY MVFR CEILINGS THAT DEVELOP WILL BE
HANDLED BY TIMELY FORECAST AMENDMENTS. VFR CONDITIONS SHOULD PREVAIL
AT EYW AND MTH WEDNESDAY. SUSTAINED SOUTH TO SOUTHWEST WINDS OF 5 TO
10 KNOTS FROM JUST OFF THE SURFACE TO ABOUT 5000 FEET WILL BACK TO
MORE OF AN EASTERLY DIRECTION AND INCREASE TO 10 TO 15 KNOTS
WEDNESDAY AFTERNOON.

&&

.CLIMATE...
ON THIS DATE IN KEYS WEATHER HISTORY...IN 1900...2.62 INCHES OF RAIN
FELL IN KEY WEST. THIS SET THE DAILY RECORD FOR MAXIMUM RAINFALL
MEASURED IN KEY WEST ON MAY 15TH...A RECORD WHICH STILL STANDS 112
YEARS LATER. RAINFALL RECORDS AT KEY WEST DATE BACK TO 1871.

&&

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

PUBLIC/MARINE.........MSB
AVIATION/NOWCASTS.....BS
DATA COLLECTION.......ULRICH

VISIT US ON THE WEB AT WWW.WEATHER.GOV/KEYWEST

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE KEY WEST FL
433 AM EDT TUE MAY 15 2012

FLZ076>078-GMZ031>034-042>044-052>055-072>075-161000-
MONROE UPPER KEYS-MONROE MIDDLE KEYS-MONROE LOWER KEYS-
FLORIDA BAY INCLUDING BLACKWATER AND BUTTONWOOD SOUNDS-
BAYSIDE AND GULF SIDE FROM CRAIG KEY TO HALFMOON SHOAL OUT TO
5 FATHOMS-
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-
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-
433 AM EDT TUE MAY 15 2012

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

.DAY ONE...TODAY AND TONIGHT

ISOLATED THUNDERSTORMS ARE POSSIBLE ACROSS THE OFFSHORE GULF WATERS
AND THE WESTERN FLORIDA STRAITS TODAY...AND ARE POSSIBLE THROUGHOUT
THE KEYS AND THE SURROUNDING COASTAL WATERS TONIGHT. THE PRIMARY
HAZARDS WILL BE CLOUD TO SURFACE LIGHTNING STRIKES AND GUSTY WINDS.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

ISOLATED THUNDERSTORMS ARE POSSIBLE FROM WEDNESDAY THROUGH FRIDAY
ALONG THE FLORIDA KEYS AND SURROUNDING COASTAL WATERS. THE PRIMARY
THUNDERSTORM HAZARDS WILL BE CLOUD TO SURFACE LIGHTNING STRIKES AND
LOCALLY GUSTY WINDS.

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME FOR FRIDAY NIGHT
THROUGH MONDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT ANTICIPATED.