THEWEATHERMOGIL:: Lake effect snow with and without lakes
Lately, there have been lots of posts at NEWxForum about “lake effect” snow. Such snows are typically found downwind from large, relatively warm lakes during periods when cold air moves across the lakes. The longer the overwater trajectory, the more linear the developing snow band, and the more persistent the wind flow, the greater the likelihood of concentrated zones of heavy snow. The snow bands lie along the prevailing low-level wind flow.
The Great Lakes and Great Salt Lake in Utah are among the places where such snow events often occur. This Monday morning (Jan. 4, 2016), it is easy to see snow bands (Fig. 1) across Lake Ontario and some isolated bands emanating from lakes in eastern New York State and Vermont (i.e., Lake Champlain).
There is one other place where lake effect snow banding is expected to develop today. That is actually in a place without a lake. In Fig. 1, that area lies off the Massachusetts coast. By late morning, snow bands had already started to develop, although they are partially masked by higher-level clouds. Here, arctic air from a strong cold frontal passage yesterday afternoon and evening (see Jake Mulholland’s blog about the “ARCTIC COLD FRONT” late on Jan. 3, 2016), is pouring out over rather warm (low to mid 40’s) ocean waters (Fig. 2). As a result, the National Weather Service (NWS) has posted winter weather advisories (2 to 4 inches of snow) for the Cape Cod area from midday today through early tomorrow morning.
A shout out goes to Matthew Cappucci, one of my meteorological interns, who flagged this story in a phone conversation yesterday afternoon. Matthew is a college freshman this year, having already conducted research on New England waterspouts and U.S. hurricane landfall patterns.
© 2016 H. Michael Mogil
Originally published 1/4/16