Heavy rain showers produced local highway flooding from standing water in Key Largo.
Every event with a place to put it. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS KEY wrote it up.
Heavy rain showers produced local highway flooding from standing water in Key Largo.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Key West, FL wrote its last area forecast discussion before the first event at May 24, 10:17 AM EST, 13 minutes earlier.
AREA FORECAST DISCUSSION FOR THE FLORIDA KEYS NATIONAL WEATHER SERVICE KEY WEST FL 1117 AM EDT THU MAY 24 2012 .DISCUSSION... .CURRENTLY...KBYX RADAR SHOWS AN EXTENSIVE BAND OF MODERATE TO HEAVY SHOWER AND THUNDERSTORM ACTIVITY FROM THE FLORIDA STRAITS...30 NM TO THE SOUTHWEST OF MARATHON ACROSS MUCH OF THE MIDDLE AND UPPER KEYS. THIS BAND IS ONE OF TWO BROAD CONVERGENT BOUNDARIES SITUATED OVER THE UPPER KEYS...FLORIDA STRAITS AND WESTERN BAHAMAS. THESE BANDS HAVE BEEN PRODUCING VERY HEAVY RAIN RATES AROUND THE REGION...WITH UP 2+ INCHES PER HOUR BEING REPORTED OVER SOME LAND AREAS. THE RADAR RETURNS THAT CORRESPOND TO THESE LAND AREAS ARE NOT SEEING THE STRONGEST OF THE RETURNS...SO IT IS BELIEVED THAT EVEN MORE TORRENTIAL DOWNPOURS ARE OCCURRING OVER THE COASTAL WATERS. ISOLATED LIGHTNING STRIKES HAVE OCCURRED WHICH IS SURPRISING FOR THE RAIN RATES GENERATED...BUT THIS MIGHT WELL HAVE BEEN EXPECTED WITH A WARM SOUNDING THROUGHOUT...AND A VERY SKINNY CAPE PROFILE. WINDS ARE VARIABLE ACROSS THE REGION...WITH NORTH TO NORTHEASTERLY WINDS REPORTED OVER THE LOWER KEYS AND POINTS WESTWARD...AND MAINLY SOUTHEASTERLY WINDS IN THE CONVERGENT BOUNDARIES SOUTH OF THE MIDDLE AND UPPER KEYS. VISIBLE SATELLITE IMAGERY SHOWS A SIGNIFICANT SWIRL IN THE CLOUD COVER AND SHOWER ACTIVITY CENTERED NEARLY OVER THE SEVEN MILE BRIDGE. WHILE THIS CIRCULATION IS NOT EXPLICITLY CLOSED ON ITS SOUTHERN EXTENT...AND MUST ACCORDINGLY BE CHARACTERIZED AS A SHORT WAVE...AT THIS POINT...THOUGH WARM RAIN PROCESSES ARE CLEARLY DOMINATING THE SHOWER ACTIVITY AROUND THE REGION. .SHORT TERM...PERIODS OF HEAVY RAIN WILL CONTINUE TO AFFECT THE MIDDLE AND UPPER KEYS THROUGH ABOUT 2 PM. AT THAT TIME THE SHORT WAVE IS EXPECTED TO PUSH NORTH AND WEST OF THE KEYS ISLAND CHAIN AND COASTAL WATERS...AND SWIRLY WINDS WILL DOMINATE THE REGIONAL WEATHER PATTERN. MODERATE LOW LEVEL INSTABILITY SHOULD MAKE FOR EASY DEVELOPMENT OF LOW TOPPED WIDESPREAD SMALL SHOWERS OVER THE COASTAL WATERS... BUT UNTIL THE WINDS SUBSIDE OVER THE ISLAND CHAIN EARLY IN THE EVENING...ARE NOT EXPECTING MUCH IN THE WAY OF STRONG CLOUD LINE SHOWER OR THUNDERSTORM DEVELOPMENT. THE ONLY MINOR CHANGE IN THIS FORECAST PACKAGE WAS TO INCREASE THE WINDS OVER THE FLORIDA STRAITS SOUTH OF THE UPPER KEYS && .MARINE...WINDS WERE FRESH TO STRONG OVER THE COASTAL WATERS SOUTH OF THE MIDDLE AND UPPER KEYS... WHILE MOLASSES REEF LIGHT HAS BEEN REPORTING 25 KNOT WINDS CONSISTENTLY ON TOP OF THE TOWER...EXPECT THAT NEAR SURFACE WINDS ARE LESS THAN THAN AND THEIR GREATEST INTENSITY WILL BE SHORT LIVED. AS SUCH...ADDED CAUTIONARY WORDING TO THE FORECAST FOR THOSE ZONES... AND ADDED EXTRA WORDING FOR THE POSSIBILITY OF STRONGER GUSTS IN SHOWERS OR THUNDERSTORMS... EXPECT A GRADUAL DROP OFF IN THE WINDS SHORTLY AFTER NOON. && .AVIATION... IFR OR LOWER CONDITIONS WILL END AT MTH BY NOON AT THE LATEST. MVFR CEILINGS ARE LIKELY AT EYW THIS AFTERNOON. BRIEF...MVFR CONDITIONS ARE CONCEIVABLE AT MTH THIS AFTERNOON. DUE TO THE SHORT-LIVED NATURE OF POSSIBLE MVFR CONDITIONS...ONLY VFR CONDITIONS WILL BE ADVERTISED IN THE MTH TERMINAL FORECAST THIS AFTERNOON. MVFR CONDITIONS ARE POSSIBLE AT EYW AND MTH TONIGHT. FORECAST CONFIDENCE OF MVFR CONDITIONS TONIGHT IS NOT HIGH ENOUGH TO INCLUDE IN THE EYW AND MTH TERMINAL FORECASTS AT THIS TIME. && .CLIMATE... ON THIS DATE IN KEYS WEATHER HISTORY...IN 2008...THE LOW TEMPERATURE AT KEY WEST INTERNATIONAL AIRPORT WAS ONLY 82 DEGREES. THIS TIED THE DAILY RECORD FOR WARMEST MINIMUM TEMPERATURE MEASURED IN KEY WEST ON MAY 24TH. IN ADDITION...THIS LOW TEMPERATURE OF 82 DEGREES IS TIED AS THE WARMEST MINIMUM TEMPERATURE EVER RECORDED IN KEY WEST DURING THE MONTH OF MAY. TEMPERATURE RECORDS IN KEY WEST DATE BACK TO 1872. && .KEY WATCHES/WARNINGS/ADVISORIES... FL...NONE. GM...NONE. && PUBLIC/MARINE.........MSB AVIATION/NOWCASTS.....BS DATA COLLECTION.......ROTHWELL VISIT US ON THE WEB AT WWW.WEATHER.GOV/KEYWEST
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE KEY WEST FL 927 AM EDT THU MAY 24 2012 FLZ076>078-GMZ031>034-042>044-052>055-072>075-251000- 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- 927 AM EDT THU MAY 24 2012 THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE FLORIDA KEYS AND ADJACENT COASTAL WATERS. .DAY ONE...TODAY AND TONIGHT ISOLATED THUNDERSTORMS ARE POSSIBLE ESPECIALLY ACROSS THE UPPER KEYS AND THE ADJACENT WATERS TODAY AND TONIGHT. THE PRIMARY HAZARDS WILL BE OCCASIONAL CLOUD TO SURFACE LIGHTNING STRIKES AND GUSTY WINDS. PERSISTENT HEAVY RAIN OVER PORTIONS OF THE MIDDLE AND UPPER KEYS MAY CREATE LOCALIZED STANDING WATER IN LOW LYING AREAS AND SIGNIFICANT PONDING ON ROADWAYS. .DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY ISOLATED THUNDERSTORMS WILL BE POSSIBLE ACROSS THE FLORIDA KEYS AND THE SURROUNDING COASTAL WATERS THROUGH THE PERIOD. THE PRIMARY THUNDERSTORM HAZARDS WILL BE CLOUD TO SURFACE LIGHTNING STRIKES AND LOCALLY GUSTY WINDS. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT ANTICIPATED.
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE KEY WEST FL
915 AM EDT THU MAY 24 2012
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0851 AM NON-TSTM WND GST 8 SSE KEY LARGO 25.01N 80.38W
05/24/2012 M40 MPH GMZ052 FL C-MAN STATION
THE MOLASSES REEF C-MAN STATION RECENTLY REPORTED A WIND
GUST OF 35 KNOTS...ASSOCIATED WITH A PASSING RAIN SHOWER.
&&
CLRSPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE KEY WEST FL 919 AM EDT THU MAY 24 2012 FLZ076-241430- MONROE UPPER KEYS- INCLUDING THE COMMUNITIES OF...KEY LARGO 919 AM EDT THU MAY 24 2012 ...STANDING WATER ON THE OVERSEAS HIGHWAY IN THE UPPER KEYS... AT 915 AM EDT...A STORM SPOTTER IN THE UPPER KEYS NEAR MILE MARKER 104 HAS MEASURED AT LEAST THREE INCHES OF RAINFALL THIS MORNING. THERE IS ABOUT THREE TO FOUR INCHES OF STANDING WATER ON THE OVERSEAS HIGHWAY NEAR MILE MARKER 104. THE BAND OF HEAVY RAINFALL CURRENTLY OVER THE UPPER KEYS WILL LIFT NORTHWARD TOWARD THE SOUTH FLORIDA PENINSULA AND HEAVY RAINFALL IN THE UPPER KEYS IS EXPECTED TO END SHORTLY. BS
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE KEY WEST FL
1018 AM EDT THU MAY 24 2012
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0909 AM NON-TSTM WND GST 8 SSE KEY LARGO 25.01N 80.38W
05/24/2012 M43 MPH GMZ052 FL C-MAN STATION
A WIND GUST OF 37 KNOTS...OR 43 MPH...OUT OF THE
SOUTH-SOUTHEAST WAS MEASURED AT THE MOLASSES REEF LIGHT
C-MAN STATION AS A BAND OF HEAVY RAINFALL PASSED NORTH OF
THAT LOCATION.
&&
BSThe national radar mosaic for the moment the first event began.
1 heavy rain. Local standard time, as filed.
One southbound lane of U.S. Highway 1 was closed due to standing water from heavy rain.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Florida in 2012Every state in 2012This day in weather historyWarnings in Florida, May 2012
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 386965.