Prime feature: Single band of snow oriented southeast of Lake Ontario with an upstream connection to Lake Huron and Lake Superior.
This event unfolded behind an upper level shortwave trough that dropped several inches of synoptic snow across the region on Super Bowl Sunday. A cold airmass, with moderate lake instability was entrenched across the lakes, even before this shortwave trough moved through. By Sunday evening the shortwave had advanced east of Lake Erie and lake effect snow developed quickly. Over Lake Ontario a band of snow formed through the evening hours, reaching the southeastern shoreline late in the evening.
A 270-280 flow over Lake Erie brought a disorganized band of lake effect snow across the Southern Tier, which brushed by far southern Erie and Wyoming Counties as winds backed slightly. Even though there was broken ice cover on the lake several inches of pure lake effect snow fell on top of the synoptic snow Sunday evening and into Monday. Due to some ice on the lake and a low inversion height, the band of snow never grew to a major impactful state, but rather produced manageable snowfall rates across the Southern Tier.
Two factors allowed a band of snow to become more impactful to the south and east of Lake Ontario. The slightly warmer lake allowed for higher inversion heights, close to ten thousand feet. More importantly within this ten thousand foot layer the band of snow was able to connect to a plume of lake effect snow off both Lake Huron and farther upstream to Lake Superior. This lead to snowfall rates in excess of 2 inches per hour, and with a 280 to 290 flow this band of snow dumped several feet of lake snows through the course of Monday across Cayuga County and Oswego County. At times, the slight northerly component to the wind allowed the band of lake effect snow to brush the southern shoreline of Lake Ontario, with areas along the immediate shoreline west of Rochester receiving up to 4 inches of snow.
Diminishing lake instability and drier air allowed the lake effect band off both lakes to fall apart during the evening hours Tuesday off Lake Erie, and overnight Tuesday night off Lake Ontario.
There was little impact on areas east of Lake Erie as snowfall rates remained tamed. Off Lake Ontario a greater snowfall rate did lead to localized traffic problems though nothing major. With much of the snow falling on Sunday evening and night and only localized high
snowfall totals this event will earn a two ** star rating.
Here are some representative reports.
Off of Lake Erie...