What do we look at when trying to find these changes from a warm pattern to a cold one?
The first indicators are from way up north in Canada, the North Pole and Russia. As the highs and lows travel around the earth, they often get into a pattern. Recently, the highs have been present over the eastern US. Over the next several weeks, the highs are shifting to the west and the lows (troughs or fronts) are replacing it. The center low is over northern Canada. This "Canadian Low" acts as the "center of the wagon wheel" swinging down "Alberta Clippers" with widespread small snowfalls. See the graphic below.
The "warmer" pattern has held off the formation of ice over Hudson Bay
Here are the temperature trends for early this week and into the weekend for the US and Canada. Notice the "32 degree" marker well north of Ohio in the first graphic then well south in the second. Much colder for sure!
Winter is coming!