Ground‐based weather radar from Peachtree City, GA, is used to examine the distribution of summer precipitation in northern Georgia, including metropolitan Atlanta, during June–August of 2002–2006. The study included 194 “synoptically benign” days with a maritime tropical air mass type. Areas in eastern metropolitan Atlanta are shown to have 30% more rainfall during these days than areas west of the city. Both precipitation amount and frequency were enhanced up to 80 km to the east of the urban core of Atlanta. A precipitation maxima northeast of Atlanta occurs near a precipitation anomaly and lightning flash density anomaly identified in previous studies. An hourly analysis of precipitation data demonstrates that the enhanced precipitation on the periphery of the urban core is most evident from 00–05 UTC (19‐00 LST). This study is the first to use ground‐based radar precipitation estimates in an attempt to quantify the impact of urbanization on precipitation.

A 44-yr climatology of nonconvective wind events (NCWEs) for the Great Lakes region has been created using hourly wind data for 38 first-order weather stations during the months of November through April. The data were analyzed in terms of the two National Weather Service (NWS) criteria for a high-wind watch or warning: sustained winds of at least 18 m s Ϫ1 for at least 1 h or a wind gust of at least 26 m s Ϫ1 for any duration. The results indicate a pronounced southwest quadrant directional preference for nonconvective high winds in this region. Between 70% and 76% of all occurrences that satisfied the NWS criteria for NCWEs were associated with wind directions from 180°through 270°. Within the southwest quadrant, the west-southwest direction is preferred, with 14%-35% of all NCWEs coming from this particular compass heading. This directional preference is borne out in five out of six stations with high occurrences of cold-season NCWEs (Buffalo, New York; Dayton, Ohio; Lansing, Michigan; Moline, Illinois; Springfield, Illinois). Given the geographic spread of these stations, a nontopographic cause for the directional preference of cold-season NCWEs is indicated. The connection between NCWEs and low pressure systems found in this climatology and in case studies suggests that midlatitude cyclone dynamics may be a possible cause of the directional preference.

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