Snowstorm Enhanced by Standing Atmospheric Wave - Duluth, MN

January 23 to 26, 2010

A prolonged snow event began on Saturday the 23rd as freezing rain which changed to sleet and then mostly snow depending upon elevation. Most of the heaviest snow fell from daybreak Sunday morning into early afternoon. Temperatures around freezing resulted in heavy weight wet snow. Periods of lighter snow continued from the rest of the day into Monday then finally ended around midnight Tuesday the 26th.

Snow accumulated much less in lower elevations since temperatures were a few degrees warmer. Only 2 to 6 inches accumulated near the immediate lakeshore while 12 or more inches accumulated along and inland of the ridge crest. Officially 13.7 inches fell at the National Weather Service office.

A rare event added 1 to 2 inches of additional accumulation at the end of the storm Monday evening. An apparent standing atmospheric wave induced by the north shore ridge of Lake Superior produced a period of moderate to heavy snow. Standing wave (or gravity wave) events are not unusual but rarely does the snow reach the ground in Duluth at least in this observers experience since moving to Duluth in 2001. When it does, the snow is very light on the northwest fringe of the event. Usually the snow falls downstream to the southeast over the lake and adjacent sections of northwest Wisconsin.

For more discussion of atmospheric waves see the Duluth Local Influences page.

NWS Duluth, MN Radar Image Near Time of Heaviest Snow

Water Vapor Satellite Image - NOAA GOES

NWS Duluth, MN Radar Image of Standing Wave Induced Snow