Special Marine Warning 252, NWS Key West, FL

671 
FZUS72 KKEY 260231
MWSKEY

MARINE WEATHER STATEMENT
NATIONAL WEATHER SERVICE KEY WEST FL
1031 PM EDT SUN SEP 25 2011

GMZ053-054-073-074-260300-
/O.CON.KKEY.MA.W.0252.000000T0000Z-110926T0300Z/
1031 PM EDT SUN SEP 25 2011

...A SPECIAL MARINE WARNING REMAINS IN EFFECT UNTIL 1100 PM EDT...

FOR THE FOLLOWING AREAS...
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 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...

AT 1029 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A LINE OF THUNDERSTORMS...PRODUCING STRONG WINDS OVER 35
KNOTS FROM 15 NAUTICAL MILES SOUTH OF SOMBRERO KEY LIGHT TO 10
NAUTICAL MILES SOUTH OF WESTERN DRY ROCKS...MOVING SOUTHEAST AT 5
KNOTS.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

MARINERS CAN EXPECT GUSTY WINDS IN EXCESS OF 35 KNOTS...ROUGH SEAS...
DANGEROUS LIGHTNING...AND POOR VISIBILITY IN HEAVY RAIN. BOATERS
SHOULD SEEK SAFE HARBOR IMMEDIATELY...UNTIL THREATENING WEATHER HAS
PASSED.

&&

LAT...LON 2436 8177 2443 8115 2429 8105 2422 8137
      2422 8162
TIME...MOT...LOC 0231Z 304DEG 3KT 2438 8114 2436 8143
          2428 8189

$$
JOHNSON

AREA FORECAST DISCUSSION FOR THE FLORIDA KEYS
NATIONAL WEATHER SERVICE KEY WEST FL
247 PM EDT SUN SEP 25 2011

.DISCUSSION...
.CURRENTLY...
KEY WEST AND MIAMI RADAR DETECTING SCATTERED TO NUMEROUS SHOWERS
EVERYWHERE BUT OVER THE KEYS AND COASTAL WATERS...WHERE ONLY A FEW
SHOWERS ARE FOUND OVER THE NEARSHORE WATERS. THERE IS ALSO A
FAIRLY UNIFORM AREA OF RAIN BETWEEN KEY LARGO AND ANDROS ISLAND
ASSOCIATED WITH A WEAK TROF OVER THE BAHAMAS. OTHERWISE...THE FLORIDA
STRAITS BETWEEN CUBA AND THE KEYS MOSTLY CLOUD AND SHOWER FREE. WINDS
THROUGH THE MORNING HAVE BEEN CONSISTENTLY SOUTH TO SOUTHWEST BETWEEN
5 AND 10 KNOTS OVER BOTH THE WATER AND THE ISLANDS...AND THIS HAS NOT
EXACTLY BEEN FAVORABLE CONDITIONS FOR CU-LINE DEVELOPMENT.

.SHORT TERM...
OVERNIGHT AND MONDAY...THE KEYS ARE IN A COL BETWEEN A SURFACE TROF IN
THE GULF ASSOCIATED WITH A SHORT WAVE ROTATING THROUGH THE BASE OF
HIGH AMPLITUDE DEEP LOW OVER THE MISSISSIPPI VALLEY...AND A WEAK
SURFACE TROF SITTING OFF THE FLORIDA EAST COAST WHICH IS PART OF A
LARGE UPPER LEVEL DIFFLUENT AREA. BECAUSE OF THIS...THE AREA IS
SURROUNDED BY SHOWERS AND THUNDERSTORMS...BUT FEW HAVE PROGRESSED
INTO OUR MARINE WATERS. THE SHORTWAVE TO OUR WEST WILL SLOWLY
PROGRESS TOWARDS THE EAST...AND THE WEAK TROF IN THE VICINITY OF THE
BAHAMAS WILL WEAKEN FURTHER AND LOSE DEFINITION AS IN MOVES OFF
EASTWARD. AS THE SHORTWAVE MOVES EASTWARD...IT WILL ALSO BEGIN TO
WEAKEN...BUT SHOULD PROVIDE ENOUGH IMPETUS FOR SCATTERED SHOWER AND
THUNDERSTORM DEVELOPMENT. THE MODEL MOS NUMBERS REFLECT THIS WITH
POPS IN THE HIGH CHANCE TO LIKELY CATEGORIES THROUGH TOMORROW.

TUESDAY THROUGH FRIDAY...THE SYNOPTIC SETUP OVER THE EASTERN CONUS
REMAINS SOMEWHAT COMPLEX. THE FLORIDA KEYS WILL REMAIN AT THE BASE OF
THE HIGH AMPLITUDE CYCLONE AS IT PROGRESSES SLOWLY EASTWARD INTO A
BLOCKING PATTERN. THIS WILL RESULT IN WINDS OVER THE AREA BECOMING
SOMEWHAT MORE ZONAL ALOFT...BUT THE BOUNDARY AND SURFACE LAYERS WILL
REMAIN IN RELATIVE WEAK FLOW. MODEL GUIDANCE SHOWS DRY AIR WORKING
INTO THE MID LEVELS THROUGH THE PERIOD...WITH EVEN SOME DRYING OF THE
BOUNDARY LAYER WEDNESDAY AND THURSDAY. WILL HOLD POPS AT SLIGHT
CHANCE.

&&

.LONG TERM...
SATURDAY AND SUNDAY...A TROF BUILDS DOWN THE ENTIRETY OF THE EAST
COAST AS HIGH PRESSURE BUILDS INTO THE SOUTHEAST...PUSHING WHAT
APPEARS TO BE THE FIRST LEGITIMATE COLD FRONT OF THE SEASON DEEP
INTO THE FLORIDA PENINSULA. GIVEN THE EXTENDED RANGE...THERE IS MUCH
UNCERTAINTY CONCERNING THE STRENGTH AND TIMING OF THE FRONT.
REGARDLESS...HIGH PRESSURE WILL LIKELY BRIDGE INTO THE AREA BRINGING
AND INCREASE OF WINDS FROM THE NORTHEAST AS WELL AS INCREASED RAIN
CHANCES. WILL HOLD OFF ON INCLUDING THIS IN THE FORECAST PRODUCT FOR
THIS CYCLE...BUT WILL SHOW AN INCREASE IN WINDS THIS WEEKEND IN OUR
GRIDDED PRODUCTS.

&&

.MARINE...
GENTLE TO LIGHT SOUTHEAST TO SOUTHERLY BREEZES ARE EXPECTED
OVERNIGHT AND MONDAY OVER ALL COASTAL WATERS. SEAS IN THE FLORIDA
STRAITS WILL BE BELOW TWO FEET...WITH LESS THAN A FOOT EXPECTED IN
HAWKS CHANNEL. SCATTERED SHOWERS AND THUNDERSTORMS CAN BE EXPECTED AT
ANYTIME...WITH A NORTH NORTHWESTWARD MOVEMENT TO INDIVIDUAL
THUNDERSTORMS.

&&

.AVIATION...
VFR CONDITIONS ARE EXPECTED TO PREVAIL THROUGH THE PERIOD AT EYW AND
MTH. MOST OF THE CONVECTIVE ACTIVITY TODAY HAS BEEN TO THE FAR WEST
OR FAR EAST OF THE AREA...SUBSIDENCE IN THE CENTER OF THESE TWO
REGIONS HAS LIMITED THE AMOUNT OF SHOWER AND THUNDERSTORMS THAT HAVE
FORMED. SHOWER ALONG THE KEYS ARE STILL POSSIBLE, BUT WILL MAINLY
RESIDE IN THE VICINITY OF AIRPORTS. RESTRICTIONS TO MVFR OR IFR WILL
BE UNCOMMON AND BRIEF THIS EVENING.

&&

.PRELIMINARY POINT TEMPS/POPS...
KEY WEST  79  89  79  89 / 40 40 30 30
MARATHON  79  90  79  90 / 40 40 30 30

&&

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

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

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

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE KEY WEST FL
454 AM EDT SUN SEP 25 2011

FLZ076>078-GMZ031>034-042>044-052>055-072>075-261000-
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-
454 AM EDT SUN SEP 25 2011

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

.DAY ONE...TODAY AND TONIGHT

SCATTERED THUNDERSTORMS ARE EXPECTED ACROSS THE KEYS ISLAND CHAIN
AND THE ADJACENT COASTAL WATERS TODAY AND TONIGHT. THE PRIMARY
THUNDERSTORM HAZARDS WILL BE CLOUD TO SURFACE LIGHTNING STRIKES AND
LOCALLY GUSTY WINDS.

.DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY

SCATTERED THUNDERSTORMS WILL BE POSSIBLE ON MONDAY...WITH ISOLATED
THUNDERSTORMS POSSIBLE MONDAY NIGHT THROUGH SATURDAY. THE PRIMARY
THUNDERSTORM HAZARDS WILL BE CLOUD TO SURFACE LIGHTNING STRIKES AND
LOCALLY GUSTY WINDS.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT ANTICIPATED.

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE KEY WEST FL
848 PM EDT SUN SEP 25 2011

FLZ076>078-260230-
MONROE UPPER KEYS-MONROE MIDDLE KEYS-MONROE LOWER KEYS-
INCLUDING THE COMMUNITIES OF...KEY LARGO...MARATHON...KEY WEST
848 PM EDT SUN SEP 25 2011

...SLOW MOVING THUNDERSTORMS PRODUCING HEAVY RAINFALL THROUGHOUT THE
ISLAND CHAIN...

AT 844 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR DETECTED
NUMEROUS SLOW-MOVING HEAVY SHOWERS AND SCATTERED EMBEDDED
THUNDERSTORMS ACROSS A MAJORITY OF THE FLORIDA KEYS ISLAND CHAIN.
DOPPLER RADAR ESTIMATES THAT RAINFALL TOTALS ACROSS PORTIONS OF THE
ISLAND CHAIN HAVE BEEN IN EXCESS OF 2 INCHES DURING THE PAST HOUR.
LOCATIONS RECEIVING HEAVIER DOWNPOURS INCLUDE ISLAMORADA IN THE UPPER
KEYS...DUCK KEY IN THE MIDDLE KEYS...AND BOCA CHICA AND BIG COPPITT
KEYS IN THE LOWER KEYS. ADDITIONAL RAINFALL AMOUNTS OF 1 TO 3 INCHES
ARE POSSIBLE ACROSS PORTIONS OF THE MIDDLE AND UPPER KEYS DURING THE
NEXT FEW HOURS. THIS ADDITIONAL RAINFALL WILL CREATE PONDING OF WATER
ON THE OVERSEAS HIGHWAY. MOTORISTS SHOULD USE EXTRA CAUTION WHEN
DRIVING THROUGH AREAS CONTAINING STANDING WATER TONIGHT.

NELSON