The frequency, character, seasonality, and diurnal phasing of convection are important components of the climatology of a place or region. The southern Great Lakes region of the United States has been understudied in this regard. It lies within a transition zone separating western regions where nocturnal thunderstorms predominate during the warm season and eastern regions where thunderstorms occur mostly during the daytime. This makes the southern Great Lakes unique in that nocturnal and daytime convection are equally frequent during the warm months of the year. The nature and extent of the influence of lake breezes and land-water temperature differences and their relationship to the occurrence, timing, and intensity of convection is unknown for this region. This research will document, using lightning and radar observations, the convective climatology of the southern Great Lakes region at a fine temporal and spatial scale. The project will identify the differences in the statistical properties of nocturnal versus daytime convective systems, and examine the nature and extent of variations in convective frequency and timing. Differences in the meso-alpha scale and synoptic scale atmospheric environment in which nocturnal and daytime convective events form will be evaluated. This will assist in an assessment of the relative hazard to human life and property posed by convective storms in terms of potential lightning damage and the probability of heavy precipitation. The improved convective climatology resulting from this research will allow for a re-evaluation of currently proposed explanations for differences in the diurnal phasing of convective storms. The linkages identified between the statistical properties of convective storms and the large-scale environments in which they form can be employed in the short-range forecasting of convection.
A Synoptic Climatology of Warm Season Convection in the Southern Great Lakes Region