Lake effect snow developed early Christmas morning and continued continuously for about 72 hours, before diminishing late in the day on Wednesday the 27th.
Off Lake Erie, the heaviest lake effect snows with this event were mainly confined to the classic snow belt directly east of Lake Erie due to the predominate westerly flow. At the onset of the event Christmas morning, the Buffalo metro area picked up a few of inches of snow before the band pushed south and was disrupted through midday. By Christmas afternoon, the lake effect snow band intensified and made its closest approach to the Buffalo Southtowns during the duration of the event. By Christmas evening, a very robust single plume had developed with localized reports of 5 to 6 inches per hour at Perrysburg in Cattaraugus County and in southern Erie County, along with a few cloud-to-ground lightning strikes. There was considerable blowing and drifting ongoing at the time. Strong wind gusts and blowing snow also accompanied this early part of the event, with gusts 35 to 45 mph.  The westerly flow then became locked in from late on the 25th to the 27th, with a lake shore hugging band near Erie, PA that spread inland across Mayville to Perrysburg to Springville to Arcade where it lingered for nearly 2 days. Towns along the Chautauqua Ridge were heavily impacted with storm totals of three to four feet of snow, with towns reportedly struggling to keep up the persistent snow.  The snow storm tapered off late in the day on Wednesday the 27th as the flow broke the lake effect into narrow, disorganized multibands. By the evening the snow tapered off completely as high pressure and drier air moved into the lower Great Lakes. Off Lake Erie, specific snowfall reports included: 44 inches at Perrysburg; 33 inches at Colden; 31 inches at Springville; 29 inches at Cattaraugus; 25 inches at Glenwood; 15 inches at Boston; 13 inches at Silver Creek; 12 inches at Rushford, Portland, Fredonia, Franklinville and Little Valley; 10 inches at Wales and Pavilion; 9 inches at Dunkirk and Jamestown; 8 inches at Angelica, Elma and Randolph.
Off Lake Ontario, the most significant lake effect snows with this event were mainly confined to the classic snow belt directly east of Lake Ontario over the Tug Hill due to the predominate westerly flow over the course of this event. However respectable snow totals were still achieved near Watertown and southeast of the lake during fluctuations the position of the band. For the bulk of the time period from Christmas afternoon through the evening of the 26th, the lake effect band remained over the Tug Hill. Generally over three feet fell over the Tug Hill during this event, with locally up to five feet at Redfield. The band was reported to have snowfall rates of 2 to 4 inches per hour on Christmas day. By the 27th, the flow turned more northwesterly, breaking the lake effect into more narrow, disorganized multibands south of Lake Ontario. The two-day snowfall of 62.2 inches of snow at Redfield set a record for Oswego County. The previous two-day record was 57.0 inches at Bennetts Bridge in February 2008. Off Lake Ontario, specific snowfall reports included:  65 inches at Redfield; 38 inches at Mannsville; 37 inches at Lowville and Lacona; 34 inches at Glenfield; 31 inches at Oswego; 30 inches at Constableville and Highmarket; 25 inches at Port Leyden; 21 inches at Osceola and Minetto; 20 inches at Pulaski; 19 inches at Hooker; 17 inches at Watertown; 13 inches at Croghan; 11 inches at Fulton; 10 inches at Palermo and Phoenix.

Lake-Effect Snow in OSWEGO, NEW YORK
From 24-DEC-17 22:00:00 to 27-DEC-17 17:00:00 (EST-5)
Property damage: 125.00K
Crop damage: 0.00K
Reported by: COOP Observer

Lake-Effect Snow in JEFFERSON, NEW YORK
From 24-DEC-17 22:00:00 to 27-DEC-17 21:00:00 (EST-5)
Property damage: 70.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Lake-Effect Snow in LEWIS, NEW YORK
From 24-DEC-17 22:00:00 to 27-DEC-17 21:00:00 (EST-5)
Property damage: 70.00K
Crop damage: 0.00K
Reported by: COOP Observer

Lake-Effect Snow in WYOMING, NEW YORK
From 24-DEC-17 18:00:00 to 27-DEC-17 17:00:00 (EST-5)
Property damage: 50.00K
Crop damage: 0.00K
Reported by: COOP Observer

Lake-Effect Snow in SOUTHERN ERIE, NEW YORK
From 24-DEC-17 18:00:00 to 27-DEC-17 17:00:00 (EST-5)
Property damage: 65.00K
Crop damage: 0.00K
Reported by: Fire Department/Rescue

Lake-Effect Snow in CHAUTAUQUA, NEW YORK
From 24-DEC-17 18:00:00 to 27-DEC-17 17:00:00 (EST-5)
Property damage: 25.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Lake-Effect Snow in CATTARAUGUS, NEW YORK
From 24-DEC-17 18:00:00 to 27-DEC-17 17:00:00 (EST-5)
Property damage: 75.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Lake-Effect Snow in ALLEGANY, NEW YORK
From 24-DEC-17 18:00:00 to 27-DEC-17 00:30:00 (EST-5)
Property damage: 25.00K
Crop damage: 0.00K
Reported by: COOP Observer