88th Annual Meeting (20-24 January 2008)

Wednesday, 23 January 2008
Lake-effect research at SUNY Oswego
Exhibit Hall B (Ernest N. Morial Convention Center)
Scott M. Steiger, SUNY, Oswego, NY; and R. Ballentine, A. Stamm, and S. Skubis
The State University of New York (SUNY) at Oswego, NY is an ideal place to study lake-effect processes. The meteorology program at Oswego has been involved with lake-atmosphere interactions research for several decades [e.g., the Lake Ontario Winter Storms (LOWS) project in the early 1990s]. Located on the eastern shores of Lake Ontario, we experience intense lake-effect snowstorms (e.g., received over 100 inches of snow in February 2007), thundersnow, waterspouts (the lead author has witnessed over 20 spouts in the last four years), hurricane-force wind gusts and high waves, and lake/land breezes. We take advantage of this great meteorological laboratory to teach our students through observing and to conduct research to better understand the local weather, some of which has a significant impact on the public.

Ten SUNY Oswego undergraduate meteorology majors along with all four faculty members participated in a COMET grant with the National Weather Service in Buffalo, NY to improve the understanding and forecasting of lake-effect snowstorms. We obtained a version of the Weather Research and Forecasting (WRF) modeling system from our NWS partners and tested different cores (NMM, ARW) and horizontal (4, 6, 8, and 10 km) and vertical resolutions (25, 31, and 37 levels) to determine which configuration gave the best forecast of band location, width, orientation, intensity, inland extent, and curvature. Overall, the NMM outperformed the ARW core slightly. The NMM was superior in forecasting band location, whereas the ARW had a much better handle on snow band width. All model configurations showed a southward bias in band placement (~10-20 km). We also researched the diurnal variation of snow band organization and intensity and found that bands were most organized between 23 and 04 Z and were more broken around 10 Z and between 14 and 19 Z. We have used these results to improve our forecasting for the Oswego City School District and SUNY Oswego to assist in their decision to cancel classes.

We have also partnered with the NWS Buffalo to improve our understanding of lake-effect lightning. There have been about 7 days with lake-effect cloud-to-ground (CG) lightning annually since 1995. The CG flash density was largest over the eastern ends of Lakes Erie and Ontario and the nearby shorelines. The lightning was mostly associated with intense, shore parallel snow bands. Lake-effect clouds are deepest and most likely to produce lightning downwind of the longest fetch, which occurs with southwest winds over Lake Erie and west-northwest winds over Ontario. These events are most likely in the early part of the lake-effect season with a peak in November; however, they have occurred in every month from September to March. Some parameters have been found useful in forecasting lake-effect thunderstorms, including higher heights of the -10ºC level, higher lake-induced equilibrium levels, and greater depths of the -10 to -25ºC layer within the convective cloud. Visual and auditory observations of thundersnow from SUNY Oswego faculty and students show that lightning occurs more frequently than detected by the National Lightning Detection Network, implying intracloud lightning occurs in these storms.

Supplementary URL: