A low pressure system will strengthen along a track across the southern tip of Lake Michigan, a classic path for snow in Wisconsin. A southward shift in forecast snow amounts has occurred since our update yesterday at this time.
Snow is already starting in western Wisconsin and will continue tonight spreading into northern Wisconsin. 2-4" could be on the ground already by sunrise Tuesday in the northwest. The biggest impact statewide will be throughout the day/night on Tuesday until early Wednesday morning in the east. Snow could be heavy at times. The National Weather Service has issued a Winter Storm Warning for a large portion of Wisconsin where 6-10" is expected. An advisory has been issued in the south. See details below:
Storm Impacts & Timing
- Snow will be possible throughout the day Tuesday ending Tuesday night in the west, early Wednesday morning in the east. The heaviest snow generally will fall during the afternoon and evening on Tuesday. The afternoon commute on Tuesday will be the most heavily impacted.
- Heavy Snow - broad region of 6-10" for central Wisconsin. Locally higher accumulations to 12" are possible. Near-blizzard conditions are possible in northeast Wisconsin Tuesday night with the combination of 30+ MPH wind gusts and heavy/blowing snow. 3-6" expected in southern Wisconsin for locations such as Madison, Milwaukee with 1-3" around the WI/IL border where precipitation may mix with rain or freezing drizzle Tuesday morning.
- Rain to Snow - Precipitation mix with rain or drizzle in the south but will change to snow Tuesday night. Cannot rule out a rumble of thunder or thundersnow in southeast Wisconsin.
- Gusty Winds- winds gusts to 30-40MPH, weaker in the northwest. Strongest along the escarpment in eastern Wisconsin (near blizzard conditions).
- Other Notes - not enough evidence/confidence from 12z run to force 8-12" or add another snow prediction contour. Very confident with current forecast. Solid snow producer for many.
Simulated Radar Loop
Here is the NAM simulated radar loop for tonight through Wedensday morning. Time is in GMT(CST +5hr).
Breaking the Streak
At the start of today there were 22 counties that haven't had a Winter Storm Warning (per NWS criteria) in over 314 days. Several counties ended their streak today.
For the latest radar, click here
For the latest warnings & storm reports, click here
For storm chaser video of the storm, click here
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