It was a cold morning in Western Wisconsin. Most of the SkyWarn13 viewing area saw temperatures below freezing. We hit -4 in Eau Claire and -2 in La Crosse. The coldest morning of the winter thus far until tonight.
A cold front moving in from the west will switch the winds out of the northwest ushering in a fresh and stronger batch of Arctic air. Temperatures will fall into the single digits below zero. Maybe just a couple degrees colder than last night. The difference....the winds will be higher. A very cold wind at that considering it is coming out of the northwest. When the front moves through around midnight we could see wind gusts of up to 25-30 mph. The winds will be slow to back off the rest of the night blowing between 15-20 mph. That will mean we could see wind chills tonight of 20-30 degrees below zero in Western Wisconsin.
Much of the Dakotas and Minnesota are under the experimental "extreme cold warning" where wind chills could dip down as far as 35 to 45 degrees below zero. An Extreme Cold Warning is only issued for air temperatures or wind chills forecast to be in the 35 to 30 below range. In Western Wisconsin, we'll likely be shy of that but it will still be dangerously cold.
Check out this wind chill index from the National Weather Service where you can determine what the wind chill will be given the air temperature and wind speed. It also tells you how long frostbite will set in given a wind chill.
Southern portions of the viewing are that do not use the Extreme Cold Warning are under Wind Chill Advisories including La Crosse. This means wind chills will be between 20-30 degrees below zero.
We'll see some sun Thursday, but it won't help. We'll be lucky to make it above zero under this Arctic air mass. One more sub-zero and cold morning likely for Friday morning, but wind chills will not be as bad though.
This is really the first time so far this year we have seen such cold weather. Last year we already thirteen days where we went below zero and several of those times we went WELL below zero. Including tomorrow morning this will be out fourth time with a below zero morning. The record for least number of days in a winter without going below zero is 5. We should be tied with that after one more below zero morning on Friday. Stay warm!