Lake-effect snows are a well-known phenomenon in regions downwind of each of the Great Lakes. Lake-effect snows are driven by convective sensible and latent heat fluxes from the lake to the atmosphere during cold months, until such time as the lake surface is largely frozen. A number of studies have indicated parameters useful in operational forecasting of lake-effect snows: Vertical temperature differences (e.g. from the surface to 850 mb) have been used to indicate the relative instability of the air with respect to the lake. The depth of the unstable layer has been employed to estimate the vertical extent of convective cloud growth.
On November 9-14, 1996, an intense lake-effect snowstorm with up to 40 inches of wet snow resulted in considerable property damage and negative social and economic impacts in northeastern Ohio. This study examines the climatic frequency of such events for the period, 1950-1995, and details both the surface and upper air conditions giving rise to heavy lake-effect storms over Lake Erie. Atmospheric conditions on heavy lake-effect days are compared to those for weaker snows, and to non-lake-effect snow days