1. 2. 3. Northern Wisconsin Weather: Lk Superior's snow and ice. 4. 12. 15. 16. 17. 18. 19. 20. 23. 24.

25. 26. Lk Superior's snow and ice. 27. 28.

Lake effect snow overnight and today.

Winds last night began coming across Lake Superior onto the south shore and Twin Ports area.
Duluth's Vertical Wind Profiler (current NWS Duluth VWP and VWP definition) shows winds to be out of the northeast up to 5000 feet. Radar shows the snowbands to be traveling along about 65 degrees of true north.

65 degrees along the south shore provide about 240 miles of fetch across Lake Superior.

Even though the average mid-lake temperature is only 36.6 degrees, conditions are good enough to produce some lake-effect snow.

Short Term Forecast: up to 2 more inches of snow.

As of 9:00 there are reports from Ashland, Bayfield, Douglas, and Burnett counties of between 0.5 and 2 inches of snow.

Another 1 to 2 inches is expected before the winds veer enough to the east to shut the snow this afternoon.

At 9:00 I measured 0.75 inches with light snow continuing.

Lake Superior Ice.

Thin ice has been developing along the north and south shores the past 30 days. Mid-lake temperatures continue to fall lower, from 38 degrees a month ago to about 36 degrees today. This map (to the right) is from January 31st.

The freezing over of Lake Superior doesn't happen every winter. It partially froze over (96%) in 1994 and completely froze over (>99%) in 1996. It is not expected to freeze over this year, but some more arctic air would continue to add to the ice.


The map (to the left) is from the National Ice Center and shows the expected ice conditions the beginning of March 2008. Eastern Lake Superior will probably be ice-free this winter, while the western end will be ice-covered. The expected ice cover will be near normal with ice thickness to be near normal thicknesses. So while it will have less ice than we hope, the ice will be about what is expected in an average winter.

Two fun facts:

The surface area of Lake Superior is 31,700 square miles, that's about 3 Hawaiis or 464 Washington DCs.
The top inch of Lake Superior contains 529 billion gallons of water.

Snow reports on the map.

This map (to the right) is from Hourly US Weather Statistics and shows where Automatic Surface Observing Stations reported snow at 9:00.

The storm system across the Ohio Valley is still bringing snow to southern Wisconsin (15-18 inches are expected in a line from Milwaukee to Janesville) and Lake Superior is blowing some snow across the UP of Michigan, northern Wisconsin, and the Arrowhead of Minnesota.

NWS Milwaukee's page on the Feb 5-6 storm.

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