Lake Effect Summary - February 24-25, 2014
Maximum Snowfall: Lake Erie 9" (West Valley); Lake Ontario 20" (Parish)
Duration: 36 hours +/-
Prime feature: Westerly flow.
Our 13th event of the season began what would be three lake effect events for the week, with this event producing the greatest snowfall totals southeast of Lake Ontario. A broad mid-level trough over the eastern Great Lakes region allowed for progressively colder air to push southward over the Great Lakes. Temperatures at 850 hPa dropped down towards -18 to -20C Sunday night, February 23rd, and this allowed for lake instability to increase, with a lake effect snow band forming with snow falling to the east and southeast of Lake Ontario. The primary focus of this snow band was on Oswego County where upwards of 5 to 10 inches of snow fell by Monday morning the 24th. To the north, across the Tug Hill region, smaller amounts were measured with mainly an inch or less falling.
During the day Monday the cold air aloft continued to deepen while the bands of snow off Lake Ontario broadened to a multi banded structure. Also during the day Monday, multi bands of snow off Lake Michigan and Lake Superior advanced across a frozen Lake Erie and coated portions of Western New York with fresh snow through the day and overnight hours.
Monday night the band of snow intensified off Lake Ontario, and again brought the greatest snow accumulations to Oswego County. Behind a short wave zipping through the upper level flow, winds veered slightly and shifted the lake effect snow band from over the open waters of Lake Ontario to the southern shoreline of Lake Ontario for a few hours Monday evening. This brought a few inches of snow overnight to the western shoreline, while southeast of Lake Ontario, lake effect snow accumulations inched closer to a foot and a half.
The band of snow shifted northward on Tuesday, February 25th and became broad in structure and then weakened as winds backed ahead of a clipper system.