During the early morning hours of May 23, an area of low pressure entered the Upper Great Lakes Region. Substantial amounts of warm air and deep moisture entered northern Ohio from the southern United States.
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 CLE wrote it up.
During the early morning hours of May 23, an area of low pressure entered the Upper Great Lakes Region. Substantial amounts of warm air and deep moisture entered northern Ohio from the southern United States. That instability lead to widespread severe weather and flooding, which began early in the afternoon in the western portions of the county warning area and persisted late into the evening.
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 Cleveland, OH wrote its last area forecast discussion before the first event at May 23, 6:47 PM EST, 13 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE CLEVELAND OH 747 PM EDT MON MAY 23 2011 .SYNOPSIS... LOW PRESSURE OVER THE NORTHERN GREAT LAKES WILL LIFT NORTHEAST ACROSS EASTERN CANADA TONIGHT AND TUESDAY. THE ASSOCIATED COLD FRONT WILL SAG SOUTH ACROSS THE AREA EARLY TUESDAY. THE FRONT WILL THEN BECOME NEARLY STATIONARY. LOW PRESSURE WILL DEVELOP ON THE FRONT ON THURSDAY. && .NEAR TERM /UNTIL 6 AM TUESDAY MORNING/... THE HOURLY FORECAST WILL SHOW SHOWERS AND THUNDERSTORMS ESSENTIALLY FORMING A LINE ACROSS NW OHIO AND MOVING EAST- SOUTHEAST ACROSS THE FORECAST AREA LATE THIS AFTERNOON THROUGH EARLY TONIGHT. DAMAGING WIND WOULD BE THE PRIME THREAT BUT IT IS COLD ENOUGH ALOFT FOR LOCALIZED LARGE HAIL AND THERE IS JUST ENOUGH SHEAR THAT WE CANNOT RULE OUT A TORNADO. THE LOW LEVEL MOISTURE IS HIGHER OVER NE OH/NW PA WITH MORE LOW CLOUDINESS SO THERE SHOULD CONTINUE TO BE LESS HEATING AND LESS CAPE AVAILABLE ALTHOUGH THERE IS SOMEWHAT MORE SHEAR IN THIS AREA. WE MAY SEE THE ACTIVITY DECREASE AS IT REACHES EXTREME NE OH/NW PA TONIGHT. AS WET AS IT HAS BEEN...ANY THUNDERSTORM DOWNPOUR COULD PRODUCE LOCALIZED FLOODING BUT THE ACTIVITY MAY MOVE THROUGH QUICKLY ENOUGH THAT A WIDESPREAD HEAVY BASIN AVERAGE RAINFALL IS UNLIKELY. WE WILL HAVE TO WATCH AS THE ACTIVITY MAY BECOME MORE WEST TO EAST ORIENTED TONIGHT STRUNG OUT AHEAD OF THE FRONT WITH HIGHER POTENTIAL FOR TRAINING. THAT SAID... THERE SHOULD BE A DIMINISHING OF THE ACTIVITY AS THE NIGHT WEARS ON. DO NOT EXPECT THE ACTUAL FRONT TO SAG SOUTH ACROSS THE LAKESHORE COUNTIES UNTIL THE WEE HOURS OF TUESDAY MORNING ALTHOUGH THE OUTFLOW FROM THE STORMS COULD SHIFT THE WIND OFF THE LAKE WELL IN ADVANCE OF THE FRONT. && .SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY NIGHT/... TIMING OF THE NEXT ROUND (AND THE NEXT ROUND) OF SHOWERS/STORMS MAY BE PROBLEMATIC SINCE THE FRONT WILL NOT BE FAR TO THE SOUTH AND THERE COULD BE SHOWERS/SPRINKLES ALMOST ANYTIME IN THE VICINITY OF THE FRONT. THE MAJORITY OF THE SIGNIFICANT RAIN SHOULD STAY TO THE SOUTH TOMORROW AND THERE MAY BE THUNDERSTORM COMPLEXES TO THE SOUTH TO CUT OFF A LOT OF THE DEEP MOISTURE. WILL HAVE A CHANCE FOR SHOWERS ACROSS THE NORTH WITH SHOWERS LIKELY FROM AROUND THE ROUTE 30 CORRIDOR AND SOUTH. THE MODELS ARE SOMEWHAT IN AGREEMENT DEVELOPING A WAVE ON THE FRONT AND INCHING THE FRONT BACK NORTH ON WEDNESDAY INTO THURSDAY. NOT SURE IF IT WILL CLEAR THE LAKESHORE. I BET THAT WITH THE LOWEST SURFACE PRESSURES OVER THE PLAINS STATES THAT ON WEDNESDAY THE WIND WILL TRY TO STAY EAST NEAR THE LAKESHORE AND IN TOLEDO. THE FRONT MAY STILL BE NEAR THE LAKE SHORE ON THURSDAY. WITH THE SURFACE LOW APPROACHING THE THREAT OF SHOWERS/STORMS SHOULD GRADUALLY INCREASE...ESPECIALLY BY THURSDAY EVENING INTO FRIDAY. TEMPERATURES OF COURSE WILL BE TRICKY. THERE WILL BE A SIGNIFICANT DIFFERENCE WHERE THERE ARE CLOUDS AND A NORTH WIND...ESPECIALLY NEAR LAKE ERIE...COMPARED TO A SOUTH FLOW AND SOME SUNSHINE. WILL HAVE TO SPLIT THE DIFFERENCE FOR NOW AND WILL NOT GO AS COOL OR AS WARM AS IT MIGHT END UP BEING. && .LONG TERM /FRIDAY THROUGH MONDAY/... THE GFS AND ECMWF ARE IN REASONABLY GOOD AGREEMENT MOVING ANOTHER LOW PRESSURE SYSTEM ACROSS THE LOWER LAKES ON FRIDAY...EVEN THOUGH THE ECMWF CONTINUES TO BE A BIT FURTHER NORTH WITH THE TRACK OF THE LOW. THIS WILL BE FOLLOWED AGAIN BY A SECOND LOW PRESSURE SYSTEM SATURDAY NIGHT...WITH THE TRACK OF THE ECMWF NOW MUCH FURTHER NORTH THAN THE GFS. TRIED TO TIME THE PRECIP WITH THE SYSTEMS BUT THAT IS A WAG AT BEST THIS FAR OUT. AFTER THIS HOWEVER...MODELS AGAIN IN CONFLICT. GFS FINALLY BUILDS HIGH PRESSURE OVER THE AREA ON MONDAY WHILE ECMWF IS MUCH SLOWER...HOLDING OFF THE HIGH UNTIL TUESDAY. MODELS HAVE BEEN TOO FAST WITH THE RIDGE YESTERDAY SO WENT WITH THE SLOWER ECMWF. && .AVIATION /00Z TUESDAY THROUGH SATURDAY/... STRONG TO SEVERE CONVECTION MOVING THROUGH THE AREA THIS EVENING. TWO AREAS AFFECTING THE REGION. ONE ALONG THE LAKE SHORE AND ANOTHER ABOUT TO MOVE INTO THE SOUTHERN TIER OF OUR AREA. FIRST AREA ABOUT TO GET HIT IS FINDLAY AND I ANTICIPATE THIS STORM COMPLEX WILL MOVE EAST TO MANSFIELD AND AKRON CANTON. STORM MAY STAY JUST SOUTH OF YOUNGSTOWN BUT THEY COULD GET HIT BY THE OUT FLOW. PROBLEM WITH SOUTHERN TIER STORMS IS POSSIBILITY OF 60 KNOT WIND GUSTS AND LARGE HAIL. MENTIONED THIS IN THE TAFS AT FDY, CAK AND YNG. STORMS WILL MOVE OUT OF THE AREA THIS EVENING AND THEN EXPECTING SOME LOW TO MID LEVEL CLOUDS ACROSS THE FORECAST AREA DURING THE NIGHT. THEN EXPECTING IMPROVEMENT TOMORROW DURING THE DAY TO VFR CONDITIONS. WINDS SHIFTING THROUGH THE PERIOD TO NORTH NORTHWEST. .OUTLOOK...NON VFR LIKELY AT TIMES WEDNESDAY AFTERNOON THROUGH FRIDAY IN SHOWERS/STORMS. && .MARINE... SOUTH WINDS WILL CONTINUE ACROSS THE LAKE THIS EVENING ESPECIALLY ALONG THE SHORE. WILL KEEP SUSTAINED WINDS IN THE 15 TO 20 KNOT RANGE WITH SOME HIGHER GUSTS AHEAD OF APPROACHING COLD FRONT. THE COLD FRONT IS EXPECTED TO PUSH ACROSS THE LAKE BEGINNING TUESDAY MORNING SHIFTING WINDS TO THE WEST AND THEN NORTH ACROSS THE WESTERN HALF OF THE LAKE BY EARLY AFTERNOON...THEN SHIFTING WINDS LATER IN THE AFTERNOON ACROSS THE EASTERN HALF. THE FRONTAL BOUNDARY IS EXPECTED TO BECOME STATIONARY OVER THE OHIO VALLEY BY MIDWEEK AS ANOTHER LOW PRESSURE DEVELOPS OVER THE PLAINS. WINDS ACROSS THE LAKE WILL SHIFT TO THE EAST AND THE BOUNDARY WILL MOVE NEAR THE LAKE ON THURSDAY. THERE IS SOME UNCERTAINTY AS TO HOW FAR NORTH THE FRONT WILL GET LATER IN THE WEEK AS LOW PRESSURE MOVES OVER NORTHERN OHIO. FOR NOW BROUGHT THE FRONT OVER THE LAKE ON THURSDAY WITH SOME SOUTHEAST WINDS...BUT THEN TURNED WINDS MORE NORTHERLY ON FRIDAY LEANING MORE TOWARD GFS SOLUTION ON LOW TRACK AS WELL AS WELL AS SREF TREND TOWARD THURSDAY NIGHT. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...NONE. PA...NONE. MARINE...NONE. && SYNOPSIS...KOSARIK NEAR TERM...KOSARIK SHORT TERM...KOSARIK LONG TERM...DJB AVIATION...LOMBARDY MARINE...ABE
HAZARDOUS WEATHER OUTLOOK...UPDATED NATIONAL WEATHER SERVICE CLEVELAND OH 441 PM EDT MON MAY 23 2011 LEZ061-147>149-167>169-OHZ012>014-021>023-031>033-038-089-PAZ001>003- 242045- LAKE ERIE OPEN WATERS FROM RIPLEY TO BUFFALO NY-WILLOWICK TO GENEVA- ON-THE LAKE OH-GENEVA-ON-THE-LAKE TO CONNEAUT OH- CONNEAUT OH TO RIPLEY NY- LAKE ERIE OPEN WATERS FROM WILLOWICK TO GENEVA-ON-THE-LAKE- LAKE ERIE OPEN WATERS FROM GENEVA-ON-THE-LAKE TO CONNEAUT- LAKE ERIE OPEN WATERS FROM CONNEAUT OH TO RIPLEY NY-LAKE-GEAUGA- ASHTABULA INLAND-SUMMIT-PORTAGE-TRUMBULL-WAYNE-STARK-MAHONING-HOLMES- ASHTABULA LAKESHORE-NORTHERN ERIE-SOUTHERN ERIE-CRAWFORD PA- 441 PM EDT MON MAY 23 2011 THIS HAZARDOUS WEATHER OUTLOOK IS FOR LAKE ERIE...NORTHEAST OHIO AND NORTHWEST PENNSYLVANIA. .DAY ONE...TONIGHT. SEVERE THUNDERSTORMS ARE LIKELY LATE THIS EVENING INTO TONIGHT. DAMAGING WIND AND HAIL ARE LIKELY. THE RAIN COULD BE HEAVY WITHIN THE STRONGER THUNDERSTORMS. .DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY. THERE WILL BE AN INCREASED RISK FOR FLOODING THROUGH FRIDAY AS REPEATED HEAVY RAINS MAY OCCUR WITH A FRONT THAT WILL STALL ACROSS THE AREA. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION WILL LIKELY BE NEEDED. LEZ143>146-162>166-OHZ003-006>011-017>020-027>030-036-037-047-242045- RENO BEACH TO THE ISLANDS OH-THE ISLANDS TO VERMILION OH- VERMILION TO AVON POINT OH-AVON POINT TO WILLOWICK OH- LAKE ERIE OPEN WATERS FROM MAUMEE BAY TO RENO BEACH- LAKE ERIE OPEN WATERS FROM RENO BEACH TO THE ISLANDS- LAKE ERIE OPEN WATERS FROM THE ISLANDS TO VERMILION- LAKE ERIE OPEN WATERS FROM VERMILION TO AVON POINT- LAKE ERIE OPEN WATERS FROM AVON POINT TO WILLOWICK-LUCAS-WOOD-OTTAWA- SANDUSKY-ERIE OH-LORAIN-CUYAHOGA-HANCOCK-SENECA-HURON-MEDINA-WYANDOT- CRAWFORD-RICHLAND-ASHLAND-MARION-MORROW-KNOX- 441 PM EDT MON MAY 23 2011 ...SEVERE THUNDERSTORM WATCH 346 IN EFFECT UNTIL MIDNIGHT EDT TONIGHT... THIS HAZARDOUS WEATHER OUTLOOK IS FOR LAKE ERIE...NORTH CENTRAL OHIO...NORTHEAST OHIO AND NORTHWEST OHIO. .DAY ONE...TONIGHT. PLEASE LISTEN TO NOAA WEATHER RADIO OR GO TO WEATHER.GOV ON THE INTERNET FOR MORE INFORMATION ABOUT THE FOLLOWING HAZARDS. SEVERE THUNDERSTORM WATCH. SEVERE THUNDERSTORMS ARE LIKELY LATE THIS EVENING INTO TONIGHT. DAMAGING WIND AND HAIL ARE LIKELY. THE RAIN COULD BE HEAVY WITHIN THE STRONGER THUNDERSTORMS. .DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY. THERE WILL BE AN INCREASED RISK FOR FLOODING THROUGH FRIDAY AS REPEATED HEAVY RAINS MAY OCCUR WITH A FRONT THAT WILL STALL ACROSS THE AREA. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION WILL LIKELY BE NEEDED. LEZ142-242045- MAUMEE BAY TO RENO BEACH OH- 441 PM EDT MON MAY 23 2011 ...SEVERE THUNDERSTORM WATCH 342 IN EFFECT UNTIL 10 PM EDT THIS EVENING... THIS HAZARDOUS WEATHER OUTLOOK IS FOR LAKE ERIE. .DAY ONE...TONIGHT. PLEASE LISTEN TO NOAA WEATHER RADIO OR GO TO WEATHER.GOV ON THE INTERNET FOR MORE INFORMATION ABOUT THE FOLLOWING HAZARDS. SEVERE THUNDERSTORM WATCH. SEVERE THUNDERSTORMS ARE LIKELY THIS EVENING INTO TONIGHT. DAMAGING WIND AND HAIL ARE LIKELY. RAIN COULD BE HEAVY WITHIN THE STRONGER THUNDERSTORMS. THE RISK IS HIGHEST ACROSS THIS AFTERNOON AND EVENING. .DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY. THERE WILL BE AN INCREASED RISK FOR FLOODING THROUGH FRIDAY AS REPEATED HEAVY RAINS MAY OCCUR WITH A FRONT THAT WILL STALL ACROSS THE AREA. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION WILL LIKELY BE NEEDED.
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE CLEVELAND OH
641 PM EDT MON MAY 23 2011
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0633 PM TSTM WND GST 3 W AMHERST 41.40N 82.29W
05/23/2011 E60 MPH LORAIN OH COUNTY OFFICIAL
60 MPH WIND GUST.
&&
MITCHELLPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE CLEVELAND OH
708 PM EDT MON MAY 23 2011
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0655 PM HAIL ELYRIA 41.38N 82.11W
05/23/2011 E1.00 INCH LORAIN OH TRAINED SPOTTER
0659 PM TSTM WND DMG NORTH RIDGEVILLE 41.39N 82.02W
05/23/2011 LORAIN OH TRAINED SPOTTER
SEVERAL TREES AND TELEPHONE POLES DOWN ON CENTER RIDGE
ROAD.
0705 PM HAIL 1 E ELYRIA 41.38N 82.09W
05/23/2011 E1.25 INCH LORAIN OH TRAINED SPOTTER
&&
MITCHELLPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE CLEVELAND OH
720 PM EDT MON MAY 23 2011
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0650 PM HAIL ELYRIA 41.38N 82.11W
05/23/2011 E1.00 INCH LORAIN OH TRAINED SPOTTER
0713 PM HAIL 3 SW NORTH RIDGEVILLE 41.36N 82.06W
05/23/2011 E1.25 INCH LORAIN OH TRAINED SPOTTER
0713 PM HAIL NORTH OLMSTED 41.41N 81.92W
05/23/2011 E1.00 INCH CUYAHOGA OH TRAINED SPOTTER
0715 PM HAIL NORTH OLMSTED 41.41N 81.92W
05/23/2011 E1.75 INCH CUYAHOGA OH TRAINED SPOTTER
0715 PM TSTM WND DMG PARMA HEIGHTS 41.39N 81.76W
05/23/2011 CUYAHOGA OH TRAINED SPOTTER
SEVERAL BRANCHES DOWN
&&
MITCHELLPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE CLEVELAND OH
724 PM EDT MON MAY 23 2011
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0721 PM HAIL PARMA HEIGHTS 41.39N 81.76W
05/23/2011 E1.25 INCH CUYAHOGA OH TRAINED SPOTTER
&&
MITCHELLPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE CLEVELAND OH
739 PM EDT MON MAY 23 2011
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0733 PM HAIL NORTH ROYALTON 41.31N 81.75W
05/23/2011 E1.00 INCH CUYAHOGA OH TRAINED SPOTTER
0729 PM TSTM WND DMG MIDDLEBURG HEIGHTS 41.37N 81.81W
05/23/2011 CUYAHOGA OH TRAINED SPOTTER
TREES DOWN
&&
MITCHELLPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE CLEVELAND OH
748 PM EDT MON MAY 23 2011
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0745 PM HAIL TWINSBURG 41.32N 81.45W
05/23/2011 E1.00 INCH SUMMIT OH TRAINED SPOTTER
&&
MITCHELLThe Buffalo radar (KBUF), 144 km away, was scanning. The volume nearest the first event began at 00:04 UTC.
3 thunderstorm wind. Local standard time, as filed.
Thunderstorm winds downed two large trees and several large tree branches.
Thunderstorm winds downed several large trees.
Thunderstorm winds downed several large trees.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Pennsylvania in 2011Every state in 2011This day in weather historyWarnings in Pennsylvania, May 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: 315164, 315168, 315167.