Abundant moisture in place over the region with weak steering flow produced scattered slow moving thunderstorms with heavy rain. This resulted in some localized flooding.
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 TBW wrote it up.
Abundant moisture in place over the region with weak steering flow produced scattered slow moving thunderstorms with heavy rain. This resulted in some localized flooding.
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 Tampa Bay, FL wrote its last area forecast discussion before the first event at Sep 1, 12:35 PM EST, 4 hours 25 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TAMPA BAY RUSKIN FL 135 PM EDT THU SEP 1 2011 .SHORT TERM (TONIGHT-SATURDAY)... SURFACE HIGH PRESSURE OVER THE MID-ATLANTIC WILL CONTINUE TO BUILD SOUTH THROUGH FRIDAY AS A TROPICAL WAVE CHURNS IN THE EASTERN GULF OF MEXICO. CONSIDERABLE CLOUDINESS REMAINS OVER THE AREA THIS AFTERNOON AND WILL LIMIT CONVECTIVE ACTIVITY FOR THE REST OF TODAY. THIS WILL ALSO KEEP HIGHS IN THE MID TO UPPER 80S. THE REST OF THE SHORT TERM FORECAST WILL DEPEND ON THE EVOLUTION OF THE TROPICAL WAVE CURRENTLY IN THE EASTERN GULF. MODELS CONTINUE TO SHOW DIFFERING SOLUTIONS ON THE TRACK AND INTENSITY OF THE SYSTEM...BUT SEEM TO MOSTLY AGREE ON KEEPING IT WEST OF OUR AREA AT LEAST FOR THE SHORT TERM PERIOD...BUT THIS SITUATION WILL HAVE TO BE CLOSELY MONITORED OVER THE NEXT SEVERAL DAYS. DEPENDING ON HOW CLOSE THE SYSTEM IS TO OUR COAST...WE COULD SEE INCREASED CLOUD COVER AND RAIN CHANCES FOR THE END OF THE PERIOD...ESPECIALLY ALONG THE WEST COAST. OTHERWISE SCATTERED SHOWERS AND STORMS ARE EXPECTED BOTH FRIDAY AND SATURDAY...POSSIBLY TO A LESSER EXTENT ON FRIDAY AS THE SURFACE HIGH TO THE NORTH USHERS IN SOME SLIGHTLY DRIER AIR OVER THE REGION. .LONG TERM (SATURDAY NIGHT-THURSDAY)... WILL BE MONITORING THE GULF FOR THE LONG TERM PERIOD AS MODELS DEVELOP A LOW IN THE NORTHERN GULF AND MEANDER THROUGH MID-WEEK AS THERE WILL BE LITTLE STEERING FLOW...BUT MODELS VARY GREATLY IN LOCATION AND INTENSITY. ACROSS THE LOCAL AREA WEAK HIGH PRESSURE WILL SHIFT EAST AND A WEAK TROUGH WILL DEVELOP WITH DEEP MOISTURE IN PLACE ALLOWING FOR SCATTERED SHOWERS AND THUNDERSTORMS MAINLY IN THE AFTERNOON AND EVENING WITH S/SE WINDS IN PLACE. TEMPERATURES WILL BE IN THE UPPER 80S TO LOWER 90S FOR HIGHS AND LOWS WILL GENERALLY BE IN THE 70S. && .AVIATION... SCATTERED SHOWERS WERE MOVING WEST INTO CENTRAL FLORIDA AND WILL IMPACT TERMINALS FROM KTPA-KRSW BETWEEN 19-23Z. EXPECT VFR CONDITIONS TONIGHT AND FRIDAY MORNING. && .MARINE... EAST/SOUTHEAST WINDS WILL REMAIN 15 KNOTS OR LESS WITH SEAS 4 FEET OR LESS THROUGH FRIDAY. THE WEEKEND FORECAST DEPENDS ON THE EVOLUTION OF THE TROPICAL WAVE IN THE EASTERN GULF. KEPT THE ONGOING FORECAST FOR A GRADUAL INCREASE IN WINDS AND SEAS STARTING ON SATURDAY. THIS FORECAST WILL LIKELY CHANGE IN THE COMING DAYS AS THE FORECAST FOR THE TROPICAL WAVE EVOLVES...BUT SOME INCREASE IN WINDS AND SEAS IS LIKELY. STAY TUNED FOR FURTHER UPDATES. && .FIRE WEATHER... NO CONCERNS. && .PRELIMINARY POINT TEMPS/POPS... TPA 75 89 75 90 / 20 40 20 50 FMY 75 89 74 90 / 20 40 20 50 GIF 73 90 72 91 / 20 30 20 40 SRQ 75 88 76 89 / 20 40 20 50 BKV 71 90 70 90 / 20 30 20 40 SPG 77 87 77 88 / 20 40 20 50 && .TBW WATCHES/WARNINGS/ADVISORIES... FL...NONE. GULF WATERS...NONE. && SHORT TERM/MARINE/FIRE WEATHER...05/CARLISLE AVIATION...72/NOAH LONG TERM...24/COLSON
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE TAMPA BAY RUSKIN FL 506 AM EDT THU SEP 1 2011 FLZ039-042-043-048>052-055>057-060>062-065-012130- LEVY-CITRUS-SUMTER-HERNANDO-PASCO-PINELLAS-HILLSBOROUGH-POLK- MANATEE-HARDEE-HIGHLANDS-SARASOTA-DE SOTO-CHARLOTTE-LEE- 506 AM EDT THU SEP 1 2011 THIS HAZARDOUS WEATHER OUTLOOK IS FOR WEST CENTRAL AND SOUTHWEST FLORIDA. .DAY ONE...TODAY AND TONIGHT. ...THUNDERSTORM IMPACT... ABUNDANT MOISTURE COMBINED WITH DAYTIME HEATING WILL SUPPORT SCATTERED SHOWERS AND THUNDERSTORMS ACROSS ALL OF WEST CENTRAL AND SOUTHWEST FLORIDA TODAY. A VERY WEAK STEERING FLOW WILL FAVOR SLOW MOVING STORMS WHICH WILL RESULT IN SOME VERY HEAVY RAINFALL AMOUNTS IN SOME LOCATIONS. THESE HEAVY RAINS MAY PRODUCE MINOR FLOODING OF LOW LYING AND POOR DRAINAGE AREAS AS WELL AS THE PONDING OF WATER ON ROADWAYS. IN ADDITION FREQUENT CLOUD TO GROUND LIGHTNING AND GUSTY WINDS WILL ACCOMPANY THE STORMS. IF THUNDER IS HEARD OR LIGHTNING IS OBSERVED MOVE INDOORS IMMEDIATELY. ...WATERSPOUT IMPACT... ABUNDANT MOISTURE COMBINED WITH LIGHT WINDS THROUGH A DEEP LAYER OF THE ATMOSPHERE WILL BE SUPPORTIVE OF WATERSPOUT DEVELOPMENT OVER THE ADJACENT GULF WATERS TODAY. MARINERS OPERATING ON THE GULF AND INLAND WATER WAYS TODAY SHOULD BE ON THE LOOKOUT FOR WATERSPOUTS AND SEEK A SAFE HARBOR IF OBSERVED. .DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY. ...THUNDERSTORM IMPACT... SLIGHTLY DRIER AIR MOVING IN FROM THE NORTH WILL REDUCE CHANCES FOR THUNDERSTORMS OVER FAR NORTHERN AREAS ON FRIDAY WITH SCATTERED SHOWERS AND THUNDERSTORMS CONTINUING CENTRAL AND SOUTH. DURING SATURDAY AND INTO EARLY NEXT WEEK INCREASING MOISTURE WILL INCREASE CHANCES FOR SHOWERS AND THUNDERSTORMS ACROSS THE ENTIRE REGION WITH SCATTERED SHOWERS AND THUNDERSTORMS EXPECTED EACH DAY. THE MAIN HAZARDS FROM THE THUNDERSTORMS WILL BE LOCALLY HEAVY RAINS...GUSTY WINDS...AND FREQUENT LIGHTNING STRIKES. ...WIND AND SEA IMPACT... A SLOW INCREASE IN WIND AND SEAS WILL BE POSSIBLE OVER THE GULF WATERS FRIDAY NIGHT INTO THE UPCOMING HOLIDAY WEEKEND AS AN AREA OF LOW PRESSURE POSSIBLY TROPICAL IN NATURE DEVELOPS OVER THE WEST CENTRAL GULF. WIND AND SEAS WILL LIKELY INCREASE INTO THE 15 TO 20 KNOT RANGE WITH SEAS BUILDING TO 3 TO 5 FEET...ESPECIALLY IN THE OFFSHORE WATERS AND SMALL CRAFT OPERATORS SHOULD EXERCISE CAUTION AND KEEP ABREAST OF LATER FORECASTS THROUGH THE UPCOMING WEEKEND. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION WILL NOT BE NEEDED TODAY. MCMICHAEL
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE TAMPA BAY AREA - RUSKIN FL
514 PM EDT THU SEP 1 2011
FLZ051-012145-
HILLSBOROUGH-
514 PM EDT THU SEP 1 2011
...STRONG THUNDERSTORMS WILL AFFECT WESTERN HILLSBOROUGH COUNTY...
NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATES A THUNDERSTORM
LOCATED NEAR MACDILL AIR FORCE...OR NEAR TAMPA...MOVING SOUTH AT 10
MPH...WILL AFFECT MACDILL AIR FORCE...UNTIL 545 PM EDT.
GUSTY WINDS 35 TO 45 MPH WILL OCCUR. FREQUENT LIGHTNING IS EXPECTED.
TO BE SAFE GO INDOORS IMMEDIATELY. IF CAUGHT OUTSIDE...FIND A LOW
SPOT...AND STAY AWAY FROM TALL OBJECTS. TORRENTIAL RAINS WILL REDUCE
VISIBILITY TO NEAR ZERO AND WILL CAUSE PONDING OF WATER ON ROADWAYS.
&&
LAT...LON 2787 8254 2795 8255 2794 8243 2790 8244
2790 8246 2792 8248 2786 8248 2784 8246
2781 8246 2783 8254 2785 8257 2787 8256
TIME...MOT...LOC 2114Z 008DEG 7KT 2788 8248The national radar mosaic for the moment the first event began.
3 heavy rain. Local standard time, as filed.
A trained spotter reported minor street flooding southwest of Largo due to heavy rains.
A trained spotter reported street flooding near the intersection of Ulmerton Road and Gulf Boulevard due to heavy rains.
A trained spotter reported minor street flooding and ditches full of water due to heavy rain.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Florida in 2011Every state in 2011This day in weather historyWarnings in Florida, September 2011
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: 346965, 346969, 346977.