Strong storms moved northwest across Palm Beach County for the second day in a row as the region remained under the influence of low pressure over the Southeast Gulf of Mexico.
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 MFL wrote it up.
Strong storms moved northwest across Palm Beach County for the second day in a row as the region remained under the influence of low pressure over the Southeast Gulf of Mexico.
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 Miami, FL wrote its last area forecast discussion before the first event at May 21, 8:37 AM EST, 18 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MIAMI FL 937 AM EDT THU MAY 21 2009 .UPDATE... NOT MUCH CHANGE TO THE GOING FORECAST REASONING TODAY. SOUTH FL REMAINS IN A DRY PATCH BETWEEN ROTATING BANDS OFFSHORE IN THE GULF WATERS AND A RELATIVELY NARROW BAND OF SHOWERS/STORMS MOVING ONSHORE ACROSS FAR NE BROWARD/SE PALM BEACH COUNTIES. VISIBLE SATELLITE IMAGERY SHOWS MOSTLY SUNNY SKIES ACROSS MUCH OF THE AREA...AND THIS SHOULD ALLOW FOR WARMING INTO THE MID 80S. THIS WILL YIELD PLENTY OF INSTABILITY WITH CAPES NEARING 3000 J/KG DESPITE THE FACT THAT MID LEVEL TEMPS HAVE WARMED SINCE YESTERDAY. COMBINED WITH EXCELLENT MID/UPPER DIVERGENCE OVERSPREADING THE REGION ON THE ERN FLANK OF THE DEPARTING STACKED LOW...COULD BE QUITE AN ACTIVE AFTERNOON WITH PERHAPS MORE CONVECTIVE COVERAGE THAN YESTERDAY. THE WARMER MID LEVELS WOULD ARGUE STORMS COULD BE WEAKER THAN YESTERDAY...BUT THIS MAY BE OFFSET SOME BY THE DIVERGENCE AND VERY LOW WET BULB ZERO HEIGHTS BELOW 9000FT. AS A RESULT THE STRONGEST STORMS COULD PRODUCE SOME HAIL OR GUSTY WINDS TODAY. THE WIND PROFILE IS NOT VERY FAVORABLE FOR TORNADOES WITH WEAK OVERALL SHEAR...BUT WITH SLIGHT BACKING IN THE LOW LEVELS WITH GRADUALLY INCREASING/UNIDIRECTIONAL SOUTHERLY FLOW ABOVE...CANNOT ENTIRELY RULE OUT A VERY BRIEF/WEAK SPIN-UP. /STRASSBERG && .PREV DISCUSSION... /ISSUED 740 AM EDT THU MAY 21 2009/ AVIATION...VFR WILL PREVAIL. TSRA IS EXPECTED TO DEVELOP LATE MORNING/AFTERNOON...BUT SINCE THE FOCUS IS EXPECTED TO BE INLAND...MAINTAINED JUST VCTS. THERE IS A CHC OF SHOWERS EAST COAST EARLY THIS MORNING. WINDS WILL PREVAIL OUT OF THE E-SE NEAR 12 KT WITH GUSTS UP TO 20 KT THIS AFTERNOON...ESPECIALLY EAST COAST. /GR PREV DISCUSSION... /ISSUED 500 AM EDT THU MAY 21 2009/ DISCUSSION...THIS MORNING AN AREA OF LOW PRESSURE AT THE SURFACE IS CENTERED AROUND 300 MILES NORTH OF COZUMEL WHILE IN THE UPPER LEVELS AN AREA OF LOW PRESSURE REMAINS JUST WEST OF THE WEST CENTRAL FLORIDA COAST. TODAY THE SURFACE LOW IS EXPECTED TO CONTINUE SLOWLY MOVING AWAY FROM FLORIDA AND TOWARD LOUISIANA WHILE THE MID TO UPPER CUT-OFF LOW REMAINS JUST WEST OF THE WEST CENTRAL FL COAST. WITH THE UPPER LOW SLIGHTLY FARTHER AWAY FROM S FL TODAY THE MID LEVEL TEMPS HAVE WARMED SOMEWHAT (FROM AROUND -13C TO AROUND -9C) AND THIS MAY KEEP AFTERNOON TSRA SLIGHTLY MORE MILD THAN YESTERDAYS ACTIVITY OVER THE INTERIOR, HOWEVER WITH UPPER DIVERGENCE AND A MOIST BOUNDARY LAYER AN ISOLATED STRONG STORM MIXED IN THE THE WIDESPREAD SHRA/TSRA CAN NOT BE RULED OUT ESPECIALLY WHEN CONVECTION INITIALLY GETS GOING THIS AFTERNOON. OF COURSE THIS IS ASSUMING THAT THE CONVECTION AND CLOUD COVER THAT IS ONGOING OVER THE INTERIOR NOW, CLEARS LONG ENOUGH THIS MORNING TO ALLOW FOR SOME HEATING THROUGH THE MORNING AND INTO THE EARLY AFTERNOON. AMPLE LOW LOW LEVEL MOISTURE AND DIVERGENCE ALOFT IS EXPECTED TO LEAD TO NUMEROUS SHRA AND TSRA ONCE AGAIN FRIDAY MAINLY OVER THE INTERIOR. ALONG THE COASTAL AREAS TODAY AND FRIDAY SHOWERS AND THUNDERSTORMS ARE EXPECTED, HOWEVER WITH TEMPS SLIGHTLY COOLER FROM THE PROXIMITY TO THE OCEANS, THESE AREAS OR THEREFORE SLIGHTLY MORE STABLE IN THE AFTERNOON... AKA LESS COVERAGE. THIS WEEKEND THROUGH THE REMAINDER OF THE FORECAST... THE CUT OFF LOW/SURFACE LOW DUO WILL MOVE INTO THE NORTH CENTRAL GULF COAST AND FINALLY ALLOW S FL TO SETTLE INTO MORE NORMAL/CLIMO LIKE PATTERN WHERE CONVECTION WILL MOST LIKELY BE SEA BREEZE AND OUT FLOW BOUNDARY INDUCED. MARINE...THE PRESSURE GRADIENT AROUND THE AREA OF LOW PRESSURE THAT IS CENTERED AROUND 300 MILES WEST SOUTHWEST OF NAPLES AND AROUND 300 MILES NORTH OF COZUMEL WILL KEEP A MODERATE TO FRESH SOUTHEAST FLOW ACROSS THE COASTAL WATERS OF SOUTH FLORIDA TODAY AND FRIDAY. THIS WEEKEND AND THROUGH THE FIRST PORTION OF NEXT WEEK THE GRADIENT WILL RELAX ALONG WITH THE WINDS. FIRE WEATHER...NO PROBLEMS OR CONCERNS. && .PRELIMINARY POINT TEMPS/POPS... WEST PALM BEACH 84 76 83 74 / 70 40 40 40 FORT LAUDERDALE 84 75 84 74 / 50 40 40 40 MIAMI 86 76 85 75 / 50 40 40 40 NAPLES 86 70 87 70 / 60 40 50 40 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. GM...NONE. && LONG TERM...04/AT SHORT TERM/AVIATION...57/DG
HAZARDOUS WEATHER OUTLOOK FOR SOUTH FLORIDA...UPDATED NATIONAL WEATHER SERVICE MIAMI FL 900 AM EDT THU MAY 21 2009 FLZ063-066>075-168-172>174-220200- GLADES-HENDRY-INLAND PALM BEACH-METRO PALM BEACH-COASTAL COLLIER- INLAND COLLIER-INLAND BROWARD-METRO BROWARD-INLAND MIAMI DADE- METRO MIAMI DADE-MAINLAND MONROE-COASTAL PALM BEACH- COASTAL BROWARD-COASTAL MIAMI DADE-FAR SOUTH MIAMI DADE- 900 AM EDT THU MAY 21 2009 ...HIGH RISK OF RIP CURRENTS CONTINUES AT THE ATLANTIC BEACHES... ...A FEW STRONG STORMS INTERIOR THIS AFTERNOON... THIS HAZARDOUS WEATHER OUTLOOK IS FOR SOUTH FLORIDA. .DAY ONE...TODAY AND TONIGHT RIP CURRENTS: EAST SOUTHEAST WINDS OF 15 TO 20 MPH ACROSS THE ATLANTIC WATERS WILL LEAD TO A HIGH RISK OF RIP CURRENTS AT THE ATLANTIC BEACHES OF PALM BEACH, BROWARD, AND MIAMI DADE COUNTIES. SWIMMING IS NOT RECOMMENDED. THUNDERSTORMS: SCATTERED TO NUMEROUS THUNDERSTORMS WILL AFFECT THE AREA, WITH THE STORMS EXPECTED TO BE MOST CONCENTRATED ACROSS THE LAKE OKEECHOBEE REGION THIS AFTERNOON. A FEW STRONG STORMS ARE EXPECTED ACROSS INTERIOR AREAS, CONTAINING FREQUENT LIGHTNING STRIKES, GUSTY WINDS AND HAIL. WIND: GUSTY WINDS TO 50 MPH ARE POSSIBLE WITH THE STRONGEST STORMS THIS AFTERNOON. HAIL: HAIL TO AROUND PENNY SIZE IS POSSIBLE WITH THE STRONGEST STORMS THIS AFTERNOON. FLOODING: THUNDERSTORMS WILL BE CAPABLE OF PRODUCING VERY HEAVY RAINFALL IN A SHORT PERIOD OF TIME. THIS COULD LEAD TO LOCALIZED STREET FLOODING, ESPECIALLY WHERE STORMS CONTINUOUSLY MOVE OVER AN AREA. WATERSPOUTS: THERE IS A MODERATE RISK OF WATERSPOUTS ACROSS THE COASTAL WATERS TODAY. .DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY TYPICAL MAINLY AFTERNOON AND EARLY EVENING THUNDERSTORMS ARE EXPECTED EACH DAY, FOCUSED ACROSS INTERIOR LOCALES. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION MAY BE NEEDED ESPECIALLY FOR THE NORTHERN SECTIONS OF SOUTH FLORIDA. FOR MORE INFORMATION...VISIT THE NATIONAL WEATHER SERVICE IN MIAMI WEBSITE AT WWW.WEATHER.GOV/MIAMI. GR
The Miami radar (KAMX), 85 km away, was scanning. The volume nearest the first event began at 13:54 UTC.
1 thunderstorm wind. Local standard time, as filed.
A thunderstorm blew down 2 trees into a parking lot at the corner of Palmetto Park Rd and Powerline Rd. One car had the back window shattered. A large branch was snapped off a pine tree at Military Trail and SW 18 ST.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Florida in 2009Every state in 2009This day in weather historyWarnings in Florida, May 2009
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: 174265.