After a mild stretch, somewhat colder air will work back into Upper Michigan tonight into Friday. This air does not look particularly cold, but our pattern seems to be reloading for another arctic blast.
Currently, there is a huge, strong ridge along the West Coast (Image 1 above). This feature is forecast to remain in essentially the same spot over the next couple of weeks. As it sits in place, it will allow for colder and colder air masses to drop southward out of Siberia over the North Pole into Canada and the northern U.S. By Sunday, a pocket of bitterly cold air will be located just to our north near James Bay (Image 2). The core of the coldest air will remain to our north and east. However, it does appear we will at least be on the southwest edge of that cold pocket for a much colder start to next week.
Then next weekend, medium-range forecast models are dislodging the Mother Lode of cold into the heart of central North America again. Image 3 above is the American GFS model upper-air forecast for next Saturday. It is an extreme solution with air at least as cold as the early January outbreak flowing southward into the central U.S. This model is not alone in driving the bitter air southward. Over the last several days, all the major forecast models have been advertising intensely cold air dropping southward again. Image 4 is the European forecast model for the same time period. If anything, it is even colder than the GFS. Like I wrote yesterday, winter is far from over.