Prime feature: Weak event mixed with synoptic snow and some rain near Lake Erie…slow start but eventually well defined band east of Lake Ontario
The weak lake effect season continued downwind of Lake Erie with a second event that didn’t even manage to coat the roads in downtown Buffalo. There was some shoveable snow found just to the north of the city, and eventually further south from the Southtowns through the Boston Hills. The event began early Friday morning around 4AM December 9, with widespread light snow masking a thin lake effect band north of the Buffalo area and heading northeast into Niagara County. By morning, 2-3 inches had fallen within the band, while other locations recorded an inch or so of accumulation. The band moved little during the day, while the synoptic snow moved off to the east. However, temperatures throughout the atmosphere were warmer than originally forecast, and the band eventually began to mix with rain, which put a halt to any additional accumulations in the afternoon. The band began to move south Friday evening, with rain changing back over to snow as colder air filtered in. The band continued to slowly move to the south overnight…but there simply wasn’t enough instability or cold air aloft to produce much in the way of additional snow amounts. A thin strip of Niagara county managed to squeak out 4-6 inches, with a lack of any significant snow across the heart of the city. Additional snow overnight south of the city, with 2-4 inches across the Southtowns and Boston Hills. The band petered out early Saturday over the Western Southern Tier with 1-3 inches.
East of Lake Ontario, it took longer for cold air to filter into the region…and lake effect activity didn’t materialize until Friday night, with a loosely organized band across the St. Lawrence river. This band slowly consolidated into a better looking band over the Tug Hill by midday Saturday December 10. This band continued into Saturday evening, eventually weakening and ending altogether by Sunday. The highest snow amounts were focused over the Tug Hill, with several readings nearing a foot. Osceola topped out the snow totals, with 17 inches by the end of the event.
The synoptic scale weather features that produced the band followed the general pattern for lake snows with a 500mb trof that crossed the Great Lakes and provided a period of cold air behind the passage of a cold front. However, instead of a closed Low at 500mb, it was an open wave that moved fairly rapidly through the Great Lakes. (Fig 1). That same pattern was also evident at 850mb (Fig 2). As a result we did not maintain prime conditions for an extended period of time. Radar loops from Buffalo (Fig 3) and Montague (Fig 4) show the snow band at various stages during the event.
Considering it is early to mid December, we’ve had a rather lackluster start to the lake effect season, with another 2 ** star event with minimal impact but respectable snow amounts east of Lake Ontario. Here are some representative reports.