Out ahead of a summer cold front, an outflow boundary from previous convection interacted with a tropical air mass. Strong drying in the mid levels, aided in producing severe thunderstorms across southeast Ohio during the late afternoon.
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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 RLX wrote it up.
Out ahead of a summer cold front, an outflow boundary from previous convection interacted with a tropical air mass. Strong drying in the mid levels, aided in producing severe thunderstorms across southeast Ohio during the late afternoon.
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 Charleston, WV wrote its last area forecast discussion before the first event at Aug 20, 3:45 PM EST, 10 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE CHARLESTON WV 445 PM EDT THU AUG 20 2009 .SYNOPSIS... TROPICAL MOISTURE PREVAILS UNTIL FRIDAY WHEN A COLD FRONT PUSHES THROUGH. LOW PRESSURE ALOFT AFFECTS THE WEEKEND. && .NEAR TERM /THROUGH FRIDAY/... LEFT OVER BOUNDARY FROM CONVECTION LAST NIGHT OVER IN AND IL WILL PROVIDE A FOCUS FOR SOME CONVECTION THIS AFTERNOON IN WESTERN PORTIONS OF THE AREA. HOWEVER...STORMS WILL BE MOVING FAIRLY GOOD. WILL KEEP A CLOSE EYE ON THIS AREA FOR POSSIBLE TRAINING. COLD FRONT PUSHES THROUGH FRIDAY. WITH PLENTY OF MOISTURE IN PLACE...EXPECT TO SEE A LINE OF SHOWERS AND THUNDERSTORMS ALONG THE BOUNDARY. TIMING OF FRONT IS NOT OPTIMUM FOR STRONGER STORMS...SO WILL HOLD OFF ON FLASH FLOOD WATCH FOR NOW. WE WILL HAVE TO MONITOR THIS SITUATION CLOSELY HOWEVER. && .SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY NIGHT/... WITH THE FRONT EAST OF THE AREA THERE WAS SOME DISAGREEMENT AMONG THE MODELS ON THE PLACEMENT OF AN UPPER LEVEL FEATURE. DRIER AIR WILL CONTINUE TO FILTER INTO THE REGION BUT THE UPPER LOW WILL CREATE A POTENTIAL FOR LIGHT SHOWERS. IN ADDITION TO THE SHOWERS THUNDERSTORMS SHOULD BE CONFINED TO THE MOUNTAINS. HAVE INTRODUCED POPS INTO DAYS 2-3 TO ACCOUNT FOR ECMWF PLACEMENT OF COLD UPPER LOW NEAR SOUTHEASTERN OHIO. FAVORED A DIURNAL PRECIP PATTERN DURING THESE PERIODS. MOS GUIDE BC USED FOR TEMPS ON SAT AND SUN BUT RAISED TEMPS SLIGHTLY ON SUNDAY. && .LONG TERM /MONDAY THROUGH THURSDAY/... THE PERIOD LOOKS QUIET INITIALLY BUT A WEAK COLD FRONT LOOKS TO MOVE TOWARD THE REGION ON WEDNESDAY NIGHT INTO THURSDAY. FOLLOWED HPC GUIDE FOR POPS LATER ON THE DAY WEDNESDAY. MINOR ADJUSTMENTS TO SKY TO ACCOUNT FOR SLIGHTLY HIGHER POP DAYS 6-7. RAISED HPC MAX TEMPS SLIGHTLY ON DAY 4 AND LOWERED THEM SLIGHTLY ON DAY 5. TEMPS WERE LOWERED FROM HPC ON DAY 7 TO ACCOUNT FOR HIGHER POP. && .AVIATION /21Z THURSDAY THROUGH TUESDAY/... TROPICAL MOISTURE OVER THE REGION WILL CONTINUE TO PROVIDE SCATTERED SHOWERS AND THUNDERSTORMS UNTIL COLD FRONT PUSHES THROUGH ON FRIDAY. EXPECT A LINE OF SHOWERS AND THUNDERSTORMS ALONG THE COLD FRONT. WITH PLENTY OF MOISTURE...LOW VISIBILITIES AND CEILINGS CAN BE EXPECTED IN THE PRECIPITATION. AFTER 18Z FRIDAY... IFR CONDITIONS IN THUNDERSTORMS FRIDAY AFTERNOON ALONG THE COLD FRONT. SATURDAY NIGHT IFR CONDITIONS POSSIBLE DUE TO FOG AND OR LOW STRATUS. && .RLX WATCHES/WARNINGS/ADVISORIES... WV...NONE. OH...NONE. KY...NONE. VA...NONE. && SYNOPSIS...RPY/TJT NEAR TERM...RPY SHORT TERM...TJT LONG TERM...TJT AVIATION...RPY
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE CHARLESTON WV 424 PM EDT THU AUG 20 2009 VAZ003-004-WVZ013-015-024>028-030>040-046-047-212030- DICKENSON-BUCHANAN-LINCOLN-KANAWHA-MINGO-LOGAN-BOONE-CLAY-BRAXTON- LEWIS-HARRISON-TAYLOR-MCDOWELL-WYOMING-RALEIGH-FAYETTE-NICHOLAS- WEBSTER-UPSHUR-BARBOUR-POCAHONTAS-RANDOLPH- 424 PM EDT THU AUG 20 2009 THIS HAZARDOUS WEATHER OUTLOOK IS FOR SOUTHWEST VIRGINIA AND WEST VIRGINIA. .DAY ONE...TONIGHT. NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. .DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY. NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. .SPOTTER INFORMATION STATEMENT... NO SPOTTER ACTIVATION IS EXPECTED AT THIS TIME. KYZ101>103-105-OHZ066-067-075-076-083>087-WVZ005>011-014-016>020-029- 212030- GREENUP-CARTER-BOYD-LAWRENCE KY-PERRY-MORGAN-ATHENS-WASHINGTON- JACKSON OH-VINTON-MEIGS-GALLIA-LAWRENCE OH-WAYNE-CABELL-MASON- JACKSON WV-WOOD-PLEASANTS-TYLER-PUTNAM-ROANE-WIRT-CALHOUN-RITCHIE- DODDRIDGE-GILMER- 424 PM EDT THU AUG 20 2009 ...SEVERE THUNDERSTORM WATCH 721 IN EFFECT UNTIL 10 PM EDT THIS EVENING... THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTHEAST KENTUCKY...SOUTHEAST OHIO AND WEST VIRGINIA. .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. .DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY. NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION MAY BE NEEDED.
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE CHARLESTON WV 153 PM EDT THU AUG 20 2009 OHZ083-084-201900- JACKSON-VINTON- 153 PM EDT THU AUG 20 2009 ...STRONG THUNDERSTORMS WILL AFFECT JACKSON AND VINTON COUNTIES... AT 150 PM EDT...STRONG THUNDERSTORMS WERE ALONG A LINE FROM 8 MILES SOUTHEAST OF CHILLICOTHE TO BEAVER TO SOUTH PORTSMOUTH...MOVING EAST AT 20 MPH. WIND GUSTS TO 50 MPH AND PEA-SIZED HAIL ARE POSSIBLE WITH THESE STORMS. OTHER IMPACTED LOCATIONS INCLUDE BUT ARE NOT LIMITED TO RADCLIFFE... PETERSBURG...MABEE...EAGLE MILLS...CREOLA...BYER...ALLENSVILLE... ZALESKI...WELLSTON...OAK HILL...MCARTHUR...LAKE HOPE STATE PARK... JACKSON...HAMDEN AND COALTON. PLEASE REPORT SIGNIFICANT WEATHER TO THE NATIONAL WEATHER SERVICE BY CALLING TOLL FREE...877-633-6772...WHEN YOU CAN DO SO SAFELY. 05
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE CHARLESTON WV 246 PM EDT THU AUG 20 2009 OHZ075-076-083>086-201945- ATHENS-GALLIA-JACKSON-MEIGS-VINTON-WASHINGTON- 246 PM EDT THU AUG 20 2009 ...STRONG THUNDERSTORMS WILL AFFECT ATHENS...EASTERN VINTON... JACKSON...MEIGS...NORTHERN GALLIA AND SOUTHWESTERN WASHINGTON COUNTIES... AT 242 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED STRONG THUNDERSTORMS ALONG A LINE EXTENDING FROM 5 MILES SOUTH OF NELSONVILLE TO 6 MILES SOUTHEAST OF MCARTHUR TO 9 MILES NORTHEAST OF WHEELERSBURG...MOVING EAST AT 25 MPH. WIND GUSTS TO 50 MPH AND SMALL HAIL ARE POSSIBLE WITH THESE STORMS. VERY HEAVY RAIN WILL FALL FROM THESE STORMS...AND WILL CAUSE WATER TO POND ON ROADS AND QUICKLY FILL ROADSIDE DITCHES AND SMALL STREAMS. EXPECT INTENSE LIGHTNING FROM THESE STORMS. DO NOT SEEK SHELTER UNDER TREES WHEN LIGHTNING THREATENS...MOVE INDOORS WHEN A THUNDERSTORM APPROACHES. PLEASE REPORT SIGNIFICANT WEATHER TO THE NATIONAL WEATHER SERVICE BY CALLING TOLL FREE...877-633-6772...WHEN YOU CAN DO SO SAFELY. 21
The Cincinnati radar (KILN), 120 km away, was scanning. The volume nearest the first event began at 20:53 UTC.
8 hail, 4 thunderstorm wind, 1 funnel cloud. Local standard time, as filed.
Trees were blown down.
Strong rotation was remotely detected by weather radar. A tornado warning was in effect, but the funnel cloud did not reach the ground.
Several trees were blown down.
Trees were blown down.
Trees and large branches fell.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Ohio in 2009Every state in 2009This day in weather historyWarnings in Ohio, August 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: 191460, 191461, 191465, 191466, 191462, 191463, 191467, 191470, 191476, 191471, 191472, 191473, 191474.