A cold air mass was in place over the Great Lakes during 12 December 2013, providing for lake-effect snow across the Great Lakes. The synthetic imagery from the 4-km NSSL WRF-ARW model initialized 0000 UTC 12 December shows the various lake-effect snowbands (low-level clouds with brightness temperatures that are not that cold relative to high level clouds):
GOES visible imagery during the morning of 12 December depicts a single band across Lake Ontario:
Note the appearance of a mesoscale vortex along the band on the eastern end of Lake Ontario, soon after it appears it moves over land and loses its organization.
The mesoscale vortex can be seen in the 0.5 degree radar reflectivity data from the KTYX WSR-88D (loop courtesy of College of Dupage NEXLAB):