It wouldn't be January without really cold temperatures, but I know a lot of us are thinking that this year has been really cold. No doubt about it, this December and January have been the coldest in the last several years for the metro, but it's likely because the last several years have been usually warm. We average 2 major arctic outbreaks during the month of January. This year we all remember the first one, giving us the coldest temperatures in the last couple of decades, but it looks like another is on the way. This one won't even compare to the first of the month… so little in fact, that it would be like comparing apples to oranges… it just can't be done. However, this cold snap will still produce dangerously chilly temperatures and wind chills of 20 to 40 below zero. It will actually come in the form of two different arctic surges. The first one is already starting to arrive on Sunday… you can actually see the leading edge rolling through northern Minnesota in the infrared satellite image below.
I have circled the line that is the leading edge of the low deck of clouds. This signifies the cold air pushing southward and clouds developing instantly as the cold air interacts with the current moisture. You can see it even better on this forecast wind speed graphic. Notice the change in wind direction line and how it moves south over time.
You can almost imagine the cold air bulldozing its way south as it rushes in behind the front.
Here is another way to look at it. The following images show the 850mb temperatures (5000 feet above ground level) forecasted for certain times of the day. So this first image shows temperatures Sunday afternoon.
Looks reasonably warm right? Fairly warm looking colors across much of the region. Now look at Monday afternoon.
What a change!! Arctic air pours into the region overtaking the warmer temperatures and allowing the thermometer to drop consistently through the day Monday. There may be a brief surge of "warmer" air Wednesday before another surge of Arctic air Wednesday evening.
Still looks really cold around here Wednesday evening! It looks like it will be Friday before temperatures can warm above the single digits. Stay Warm!!!