Algonquin - Storm Summary Wed.- Thu.,  November 3 - 4, 1999

This was our first lake effect snow of the season. The snow developed in the wake of an extremely deep 28.95" low pressure system that moved north from Pennsylvania across Lake Ontario to western Quebec. The storm produced flooding rains at Buffalo and Niagara Falls and locally damaging southeast winds over parts of the higher elevations of the Genesee Valley. Typically, when a synoptic (or large) scale low ends up just south of James Bay (or southeast of James Bay in this case) the location is favorable to produce a westerly flow of cold air across the Great Lakes.

Lake effect snow bands developed Wednesday morning and produced anywhere from 2 to 4 inches across the higher elevations of Chautauqua, Cattaraugus and extreme southern Erie counties by mid-afternoon.  As is often the case with early season snows, the warm temperatures of Lake Erie and Ontario (52 degrees) kept precipitation in the form of rain within a few miles of the shoreline.

During the late afternoon and evening the Lake Erie snowband began to consolidate and strengthen a bit more across the Southern Tier.  In fact, the snow spotter from Stockton in Chautauqua county reported thunder at 3:45 PM and conditions became a bit tricky in areas like Ellicottville where snowfall totals exceed 10 inches by midnight. The consolidation from numerous less intense snowbands to one, organized band is thought to be a result of the loss of daytime heating and mixing over land. That diurnal effect tends to "mask" the full effect of the warm lake.  At night we often see the main snowband strengthen. Well after midnight however, the overwhelming synoptic scale subsidence inversion began to work its way in from the west across Lake Erie and the snowband weakened and finally dissipated.

Meanwhile, as the evening progressed at the east end of Lake Ontario, a band finally began to take shape. By 900 PM the snow spotter at Castorland (Lewis county, Tug Hill Plateau) also reported thunder. The band, aided by orographic lift, produced about 6 inches of snow by Thursday morning, with a couple of more inches early in the day before the event came to an end.

This final snowfall totals were not too shabby for such an early date.  Off Lake Erie, Ellicottville in the heart of ski country in central Cattaraugus county reported 14", while New Albion had 11", Little Valley 10", Cassadaga 5" and Arcade 4". Off Lake Ontario Montague had 9", Hooker 8", North Osceola 7.5" and Barnes Corners 3". The snow had little effect on the population in general though. Most of it fell at night, it did not hit any large metropolitan areas and no school closings were reported as a direct result of the snow, so it doesn't rate very high on the Flake Scale.

Flake Rating - **