Unusual Snowstorm of October 4 1987

On October 4, 1987, an unusual early-fall snowstorm affected eastern New York, western Massachusetts, western Conneticut and Vermont. For areas east of the Hudson River, the heaviest snow occurred between 09 and 17 UTC. Snowfall rates of 3"/hr were common in the areas of heaviest snow. There were two areas of heavy snow. One area was over the Catskill Mountains where up to 21" of snow fell. The second area extended from northeastern Westchester county, NY northward into Resssalaer county NY and then north-northeastward into southwestern Vermont. Adjacent areas of western Connecticut and western Massachusetts also received heavy snow. This is the earliest documented major snowstorm to affect eastern New York in recorded history. The event was particularly devastating since trees at lower elevations (below 2000 ft) were fully leaved. Snow collected on the leaves and the resultant weight brought down many limbs and caused several hundred thousand residents to lose power for up to a week or more. After stumbling on this event during my research of the October 9, 1979 heavy wet snowstorm, I decided that proper documentation needed to be done while the event is still in memory of area residents.

Snow Documentation

In addition to storm documentaion by the weather service (Sanders and Bosart 1993), research by LaPenta (1988) and snowfall data from the eastern New York Weather Observing Network (graphical form), strategic phone calls were made to the affected area including, town historians, local fire departments, libraries and even local residents. Although the final product is not complete, this has already resulted in a more refined snowfall map for the storm. This is currently in the form of amounts plotted in google maps. Keep in mind that most of these values were maximum snow depth measurements and not snowfall. A large map of snowfall totals with states and counties will also be developed in the near future.

Prior Meteorological Research

A nice research paper was publised in Monthly Weather Review (Sanders and Bosart 1993). LaPenta (1988) also provided some insight into this rare storm.

Meteorological Setting

A strong shortwave trough progressed southeastward from central Canada into the Great Lakes and Midwest by October 2. The system became neutrally tilted by 12 UTC October 3 over the Middle Atlantic region. The system underwent strong baroclinic development between 00 UTC 4th and 18 UTC 4th and lifted north-northeastward in negative tilt fashion. Strong surface cyclogenesis occurred with the central pressure of the surface low dropping from 1008 to 990mb.