The Impacts of the Passage of Three Distinct Short-Wave Troughs on a Prolonged Lake-Effect Snow Event during OWLeS

From 6 to 9 January 2014 during the field phase of the OWLeS project, three distinct short-wave troughs passed over Lake Ontario during a single extended lake-effect snow event. This event produced snowfall totals ranging from 6–60 inches within a 100-mile region. This presentation will give an overview of the changes in the lake-effect snow character as each short-wave trough passed. A primary focus will be on how the first, most intense short-wave trough influenced the boundary layer.

Ahead of each of these three short-wave troughs, the lake-effect snow bands tended to increase in intensity, inland extent, move southward, and even mimic the trough curvature. The sharpness and depth of each short-wave trough appeared to influence the relative changes in these characteristics. Sounding data along with MIPS observations taken during the passage of this first short-wave trough shows that the boundary-layer depth increased ahead of the trough passage both north and south of the lake-effect band. This boundary layer deepening resulted in a rapid increase in convective intensity. Following the short-wave trough passage, both the boundary-layer depth and the resulting convective intensity decreased.