A general snow across the region was enhanced by the Great Lakes before transitioning to lake effect snow bands east and southeast of the lakes.
Off Lake Erie, lake effect snow was enhanced by upslope flow along the Chautauqua Ridge in Chautauqua County, the Boston Hills of southern Erie County, and the higher terrain of Wyoming County. There was also a strong upstream connection to Lake Huron at times Tuesday night, which focused primarily on Chautauqua County. The lake effect snow taper off and ended by late Wednesday.  Specific snowfall reports included: 17 inches at Perrsyburg; 16 inches at Colden and Sardinia; 14 inches at Findley Lake; 13 inches at Forestville; 12 inches at Little Valley, Glenwood, Rochester and Mayville; 11 inches at Webster; 10 inches at Randolph and Jamestown; 9 inches at Rochester Airport; and 8 inches at Brockport, Warsaw, Allegany and Frewsburg.
Off Lake Ontario, synoptic snow became lake enhanced on Tuesday and Tuesday night, before transitioning to purely lake effect snow by late Tuesday night through Wednesday. A robust lake effect snow plume was centered on the Tug Hill under a westerly flow with snowfall rates exceeding 2 inches per hour. Overnight, winds became northwest and pushed this band to the south, breaking it apart into multi-bands on a northwest flow. The impacts late Tuesday night into Wednesday were primarily from Wayne County east through Oswego County, with an upstream connection to the Georgian Bay at times. The lake effect snow ended Wednesday night. Snowfall amounts were generally highest toward the southeast corner of Lake Ontario, which saw the most persistent lake enhancement of snowfall.  Specific snowfall reports included: 30 inches at Redfield; 21 inches at Lacona; 19 inches at Osceola and Pulaski; 18 inches at Constableville and Fulton; 16 inches at Lorraine; 15 inches at Hooker; 14 inches at Mannsville; 13 inches at Palermo; 12 inches at Carthage and Conquest; 11 inches at Minetto, Sodus, Marion, Highmarket and Port Leyden; 10 inches at Watertown; 9 inches at Walworth; and 8 inches at Redwood.

Winter Storm in MONROE, NEW YORK
From 12-DEC-17 01:00:00 to 13-DEC-17 13:00:00 (EST-5)
Property damage: 25.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

Winter Storm in WAYNE, NEW YORK
From 12-DEC-17 01:00:00 to 13-DEC-17 18:00:00 (EST-5)
Property damage: 20.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

Winter Storm in NORTHERN CAYUGA, NEW YORK
From 12-DEC-17 01:00:00 to 13-DEC-17 18:00:00 (EST-5)
Property damage: 25.00K
Crop damage: 0.00K
Reported by: Public

Winter Storm in OSWEGO, NEW YORK
From 12-DEC-17 01:00:00 to 13-DEC-17 18:00:00 (EST-5)
Property damage: 25.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

Winter Storm in JEFFERSON, NEW YORK
From 12-DEC-17 01:00:00 to 13-DEC-17 09:00:00 (EST-5)
Property damage: 30.00K
Crop damage: 0.00K
Reported by: Social Media

Winter Storm in LEWIS, NEW YORK
From 12-DEC-17 01:00:00 to 13-DEC-17 09:00:00 (EST-5)
Property damage: 35.00K
Crop damage: 0.00K
Reported by: COOP Observer

Lake-Effect Snow in WYOMING, NEW YORK
From 11-DEC-17 23:00:00 to 13-DEC-17 09:00:00 (EST-5)
Property damage: 15.00K
Crop damage: 0.00K
Reported by: COOP Observer

Lake-Effect Snow in CHAUTAUQUA, NEW YORK
From 11-DEC-17 23:00:00 to 13-DEC-17 13:00:00 (EST-5)
Property damage: 30.00K
Crop damage: 0.00K
Reported by: Social Media

Lake-Effect Snow in CATTARAUGUS, NEW YORK
From 11-DEC-17 23:00:00 to 13-DEC-17 13:00:00 (EST-5)
Property damage: 35.00K
Crop damage: 0.00K
Reported by: COOP Observer

Lake-Effect Snow in SOUTHERN ERIE, NEW YORK
From 11-DEC-17 23:00:00 to 13-DEC-17 09:00:00 (EST-5)
Property damage: 30.00K
Crop damage: 0.00K
Reported by: Trained Spotter