National Weather Service United States Department of Commerce

Lake Effect Summary - October 18, 2015


Lake Effect Snowfall - October 18, 2015




Maximum Snowfall: Lake Erie 6" (Randolph); Lake Ontario 9" (Mexico/Parish)

Duration: 6 hours +/-

Flake Scale: 1 flake*

Our lake effect snow season started quickly, with the first October event since the destructive October 12-13 event of 2006.  An early season lake effect snow band produced a narrow strip of 8 to 10 inches of snow southeast of Lake Ontario early Sunday morning the 18th of October. 

The eastern Great Lakes region was in an early season cold air advection pattern with a sharp upper level trough of low pressure over the region. The trough axis had previously crossed the region with a cold northwest flow pouring over the eastern Great Lakes. Aloft, 850 hPa temperatures dropped to -8c on the Buffalo morning sounding 12Z/18th while even colder air of -10c was to the north over Lake Ontario. Disorganized lake effect snow showers struggled to accumulate overnight when temperatures were slightly warmer and there was less moisture available. As the upper trough moved east, winds aloft shifted to the northwest and advected moisture from upstream lakes across the region. There was a weak convergent flow on eastern Lake Ontario for most of the night with southerly winds reported at Oswego, New York and winds on the northern shore from the north. Once the moisture and westerly push arrived the weak lake effect snow showers organized into a lake effect snow band which focused on a narrow line from New Haven to Parish in Oswego County. This narrow band produced up to 9 inches of snow, with little if any accumulation outside of this band. Off Lake Erie localized 6 inches of snow fell over the western Southern Tier, where upstream connection to Lake Huron brought additional moisture into the Lake Erie snow band.

Given the timing of the event, early Sunday morning, there was little impact on the general public, and much of the snow melted just a day later. This event will earn 1* flake.


Off Lake Erie...
6.0 inches... Randolph
3.0 inches... Little Valley
2.9 inches... Kennedy
1.7 inches... Frewsburg

Off Lake Ontario...
9.0 inches... New Haven
9.0 inches... Mexico
9.0 inches... Parish
5.5 inches... Hastings