Surface wind directions associated with snowfall in upstate New York

Hourly observations of snowfall, recorded during the months of November through April for thirteen seasons, 1981-82 through 1993-94 at National Weather Service stations mostly in New York State, were used to analyze the wind directions observed during those hours. It was found that wind directions were not uniformly distributed from 10 degree to 360 degree . The preferred wind directions were consistent with snow resulting from synoptic-scale systems and from lake-effect. At stations located near the Great Lakes, most snowfall hours occurred with winds which had a fetch over one of the lakes and a smaller number of hours apparently from synoptic-scale snow events. At New York City and Boston, Massachusetts, most snowfall hours were consistent with coastal snowstorms in that winds were from the north or northeast. Albany and Binghamton, two New York State inland stations located some distance from the lakes, showed characteristics of both regimes, as well as one with southeast winds which may have been due to warm-air advection. Separating the seasons into those, which could be identified as El Nino, La Nina, or neutral resulted in some differences in the wind distributions. At all stations, El Nino tended to show slightly more snowfall hours with east or northeast winds than the two other seasonal types. El Nino winters produced fewer snowfall hours with west and southwest winds than La Nina or neutral winters. This was especially pronounced at the three stations closest to the Great Lakes.