A massive convective complex moved from lower Michigan across southern Ontario near Toronto then dove southeast across the Niagara Frontier and Western Southern Tier. This followed an earlier round of strong thunderstorms and heavy rains earlier in the day. Damage from the thunderstorm winds was widespread across the Niagara Frontier and Western Southern Tier.  Trees as large as two to three feet in diameter were downed. Power outages were scattered throughout the region as the winds downed power lines.
The unprecedented heavy rains that fell���four to six inches in less than two hours���resulted in some of the worst flash flooding the area has seen. Parts of Erie, Chautauqua, Cattaraugus and Allegany counties received State and Federal Disaster Declarations. In the Village of Silver Creek an entire mobile home park along Silver Creek was washed away. The flood waters continued through the heart of the village through the fire station, police headquarters and highway department. Several police cars, an ambulance and much of the town���s highway equipment were lost. In Irving, the flood waters flowed across parts of the New York State Thruway and Routes 5 and 20. Water flooded portions of Lakeshore Hospital there. Also in Irving, the Seneca Nation sustained almost two million dollars in damage to roads and bridges. In total, in Chautauqua county hundreds of homes were damaged and 45 homes were condemned, including the 35 mobile homes of the aforementioned park. In the Village of Gowanda (part of which is in Erie County and part in Cattaraugus county), extensive flash flooding occurred. Tri-County hospital in Gowanda was inundated by flood waters. Patients were transferred to Lakeshore Hospital in Irving. Several hundred homes sustained damage and 40 homes were condemned there. One fatality occurred in Gowanda as an 80-year-old man ventured out to check a bridge on his property and was swept away by the flood waters. The gage on Cattaraugus Creek at Gowanda showed a rise from six feet to near 13 feet in less than an hour (flood stage is 10 feet). Throughout Cattaraugus county over one-quarter of the roads were damaged or lost.

Thunderstorm Wind in NIAGARA, NEW YORK
From 09-AUG-09 20:20:00 to 09-AUG-09 20:20:00 (EST-5)
Location: NEWFANE
Magnitude: 50.00 EG
Property damage: 8.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Trees and wires were downed by thunderstorm winds.

Thunderstorm Wind in ORLEANS, NEW YORK
From 09-AUG-09 20:45:00 to 09-AUG-09 20:45:00 (EST-5)
Location: RIDGEWAY
Magnitude: 50.00 EG
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Trees and wires were downed by thunderstorm winds.

Thunderstorm Wind in ORLEANS, NEW YORK
From 09-AUG-09 20:50:00 to 09-AUG-09 20:50:00 (EST-5)
Location: ALBION
Magnitude: 50.00 EG
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Trees and wires were downed by thunderstorm winds.

Thunderstorm Wind in ERIE, NEW YORK
From 09-AUG-09 20:55:00 to 09-AUG-09 20:55:00 (EST-5)
Location: WILLIAMSVILLE
Magnitude: 50.00 EG
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Public

Trees and wires were downed by thunderstorm winds.

Thunderstorm Wind in GENESEE, NEW YORK
From 09-AUG-09 21:12:00 to 09-AUG-09 21:12:00 (EST-5)
Location: BATAVIA
Magnitude: 50.00 EG
Property damage: 20.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Trees and wires were downed by thunderstorm winds.

Thunderstorm Wind in CATTARAUGUS, NEW YORK
From 09-AUG-09 22:20:00 to 09-AUG-09 22:20:00 (EST-5)
Location: ELLICOTTVILLE
Magnitude: 50.00 EG
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Trees and wires were downed by thunderstorm winds.

Flash Flood in ERIE, NEW YORK
From 09-AUG-09 22:45:00 to 10-AUG-09 00:30:00 (EST-5)
Location: SARDINIA
Flood cause: Heavy Rain
Property damage: 100.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Thunderstorm Wind in CATTARAUGUS, NEW YORK
From 09-AUG-09 22:50:00 to 09-AUG-09 22:50:00 (EST-5)
Location: ISCHUA
Magnitude: 50.00 EG
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Trees and wires were downed by thunderstorm winds.

Flash Flood in CATTARAUGUS, NEW YORK
From 09-AUG-09 23:00:00 to 10-AUG-09 01:00:00 (EST-5)
Location: WEST PERYSBURG
Flood cause: Heavy Rain
Property damage: 250.00K
Crop damage: 0.00K
Reported by: Public

Thunderstorm Wind in CATTARAUGUS, NEW YORK
From 09-AUG-09 23:20:00 to 09-AUG-09 23:20:00 (EST-5)
Location: HINSDALE
Magnitude: 50.00 EG
Property damage: 15.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Trees and wires were downed by thunderstorm winds.

Flash Flood in CHAUTAUQUA, NEW YORK
From 09-AUG-09 21:40:00 to 10-AUG-09 01:00:00 (EST-5)
Location: SILVER CREEK
Flood cause: Heavy Rain
Property damage: 30.00M
Crop damage: 0.00K
Reported by: Emergency Manager

Thunderstorm Wind in ERIE, NEW YORK
From 09-AUG-09 21:16:00 to 09-AUG-09 21:16:00 (EST-5)
Location: EBENEZER
Magnitude: 50.00 EG
Property damage: 15.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Trees and wires were downed by thunderstorm winds.

Thunderstorm Wind in LIVINGSTON, NEW YORK
From 09-AUG-09 21:20:00 to 09-AUG-09 21:20:00 (EST-5)
Location: CALEDONIA
Magnitude: 50.00 EG
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Trees and wires were downed by thunderstorm winds.

Thunderstorm Wind in WYOMING, NEW YORK
From 09-AUG-09 21:23:00 to 09-AUG-09 21:23:00 (EST-5)
Location: ATTICA
Magnitude: 50.00 EG
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Trees and wires were downed by thunderstorm winds.

Thunderstorm Wind in WYOMING, NEW YORK
From 09-AUG-09 21:32:00 to 09-AUG-09 21:32:00 (EST-5)
Location: COVINGTON
Magnitude: 50.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Trees and wires were downed by thunderstorm winds.

Thunderstorm Wind in LIVINGSTON, NEW YORK
From 09-AUG-09 21:34:00 to 09-AUG-09 21:34:00 (EST-5)
Location: AVON
Magnitude: 50.00 EG
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Trees and wires were downed by thunderstorm winds.

Thunderstorm Wind in LIVINGSTON, NEW YORK
From 09-AUG-09 21:38:00 to 09-AUG-09 21:38:00 (EST-5)
Location: LEICESTER
Magnitude: 50.00 EG
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Trees and wires were downed by thunderstorm winds.

Thunderstorm Wind in WYOMING, NEW YORK
From 09-AUG-09 21:40:00 to 09-AUG-09 21:40:00 (EST-5)
Location: STRYKERSVILLE
Magnitude: 60.00 EG
Property damage: 15.00K
Crop damage: 0.00K
Reported by: Public

Trees and wires were downed by thunderstorm winds.

Thunderstorm Wind in WYOMING, NEW YORK
From 09-AUG-09 21:41:00 to 09-AUG-09 21:41:00 (EST-5)
Location: SHELDON CENTER
Magnitude: 50.00 EG
Property damage: 8.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Trees and wires were downed by thunderstorm winds.

Thunderstorm Wind in WAYNE, NEW YORK
From 09-AUG-09 21:42:00 to 09-AUG-09 21:42:00 (EST-5)
Location: ONTARIO
Magnitude: 50.00 EG
Property damage: 15.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Trees and wires were downed by thunderstorm winds.

Thunderstorm Wind in CHAUTAUQUA, NEW YORK
From 09-AUG-09 22:05:00 to 09-AUG-09 22:05:00 (EST-5)
Location: HANOVER CENTER
Magnitude: 50.00 EG
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Trees and wires were downed by thunderstorm winds.

Thunderstorm Wind in CATTARAUGUS, NEW YORK
From 09-AUG-09 22:05:00 to 09-AUG-09 22:05:00 (EST-5)
Location: EAST OTTO
Magnitude: 50.00 EG
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Trees and wires were downed by thunderstorm winds.

Thunderstorm Wind in CATTARAUGUS, NEW YORK
From 09-AUG-09 22:05:00 to 09-AUG-09 22:05:00 (EST-5)
Location: DELEVAN
Magnitude: 50.00 EG
Property damage: 15.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Trees and wires were downed by thunderstorm winds.

Thunderstorm Wind in CATTARAUGUS, NEW YORK
From 09-AUG-09 22:10:00 to 09-AUG-09 22:10:00 (EST-5)
Location: ASHFORD
Magnitude: 50.00 EG
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Trees and wires were downed by thunderstorm winds.

Thunderstorm Wind in LIVINGSTON, NEW YORK
From 09-AUG-09 22:15:00 to 09-AUG-09 22:15:00 (EST-5)
Location: SPRINGWATER
Magnitude: 50.00 EG
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Trees and wires were downed by thunderstorm winds.

Flash Flood in WAYNE, NEW YORK
From 09-AUG-09 20:00:00 to 09-AUG-09 21:30:00 (EST-5)
Location: WILLIAMSON SODUS ARP
Flood cause: Heavy Rain
Property damage: 25.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Flash Flood in CATTARAUGUS, NEW YORK
From 09-AUG-09 22:00:00 to 10-AUG-09 01:30:00 (EST-5)
Location: GOWANDA
Flood cause: Heavy Rain
Property damage: 45.00M
Crop damage: 0.00K
Reported by: County Official

Flash Flood in ERIE, NEW YORK
From 09-AUG-09 22:00:00 to 10-AUG-09 01:30:00 (EST-5)
Location: HELMUTH
Flood cause: Heavy Rain
Property damage: 15.00M
Crop damage: 0.00K
Reported by: Emergency Manager

Flash Flood in CHAUTAUQUA, NEW YORK
From 09-AUG-09 22:55:00 to 10-AUG-09 01:00:00 (EST-5)
Location: SILVER CREEK
Flood cause: Heavy Rain
Property damage: 250.00K
Crop damage: 0.00K
Reported by: County Official