Lake effect snow was slow to organize overnight, but that has
changed now as convergence increases just ahead of the trough. An
intensifying band of lake effect snow over Watertown early this
morning will swing rapidly south across Watertown, ending up across
the central Tug Hill later this morning as boundary layer flow
briefly veers westerly. Snowfall rates will increase to 2-3 inches
per hour during this time.
Boundary layer flow will then back to the southwest again this
afternoon, carrying heavy lake effect snow back to central Jefferson
County from Watertown down the Route 3 corridor. Boundary layer flow
will then again veer westerly this evening, pushing heavy lake
effect snow back south to the Tug Hill Plateau. Snowfall rates will
continue at 2-3 inches per hour in the heaviest portion of this band
through much of the night.
Additional accumulations of 10-16 inches appear likely across much
of central and southern Jefferson County and northern Oswego County
today through tonight from several rounds of heavy snow. The
greatest accumulations will be found across the central and northern
Tug Hill where the band interacts with terrain, expect 2-3 feet of
accumulation near the triple point of Jefferson/Oswego/Lewis
counties.
The lake snow will continue through early Sunday morning, then
rapidly weaken and move north across Jefferson County from mid
morning to midday as boundary layer flow backs to the SSW and
inversion heights quickly lower