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A Climatology of Cold-Season Nonconvective Wind Events in the Great Lakes Region

2007; American Meteorological Society; Volume: 20; Issue: 24 Linguagem: Inglês

10.1175/2007jcli1750.1

1520-0442

Matthew C. Lacke, John A. Knox, John D. Frye, Alan E. Stewart, Joshua D. Durkee, Christopher M. Fuhrmann, Sarah M. Dillingham,

Tropical and Extratropical Cyclones Research

Abstract 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−1 for at least 1 h or a wind gust of at least 26 m s−1 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.