More Arctic air is on the way this week, but many of us want to know if it will persist through Christmas. As one bitterly cold blast of Arctic air pushes out of the region, another surge of frigid air is already set to move back in. We will experience a bit of a break from the really cold air this weekend. However, another surge of unseasonably cold air driven by the breakdown of the polar vortex will likely expand from central Canada through the Midwest and move into the eastern United States again by early next week. And, to make matters worse, this next blast is the first of more cold spells that may linger through the middle of December.
Polar vortexes are not something new. However, the term “polar vortex” has only recently been popularized but has always been present. It is a large area of low pressure and cold air surrounding both the Earth’s poles. It always exists near the poles but weakens in the summer and strengthens in the winter. When a storm is strong, it tends to keep the coldest air locked up over the pole. However, many times during the winter, the polar vortex will expand or stretch sending frigid air southward through Canada and over the United States. This sets the stage for those large outbreaks of Arctic air that may persist for days. We have been in this pattern since late November. This shift in the Polar Vortex is creating more opportunities for below-average temperatures to continue over the Great Lakes, which may continue in waves for another couple of weeks.
Along with these waves of Arctic air will come a parade of quick hitting Alberta Clippers.
- Alberta Clipper
These systems will line up bringing the potential for accumulating snow across much of Michigan on Tuesday and a wintry mix possible on Wednesday. The arctic air will seep back into the region likely triggering bands of lake-effect snow on Thursday. The last Clipper of this series will bring another chance for snow to wrap up the week on Friday.
This wintry pattern is expected to continue bringing rounds of snow chances through mid-month. There is some indication that the Arctic air may finally ease its grip on the state by the week of Christmas.
