The very cold Arctic-source high pressure air mass will be departing to the east today, but it could leave behind some record low temperatures Wednesday morning. Early morning temperatures in the teens area-wide will see readings in some of our colder spots drop below Chicago’s record low on this date of 14 degrees set back in 1916.
With the center of cold high pressure overhead Tuesday, our official high of only 29 degrees was below normal for even January. The cold air also set the stage for the snow earlier that spread over northwest Indiana, including 3 inches at Valparaiso, as a low pressure system passed to our south.
The upper-level jet stream flow will become more west to east, trapping colder air farther north and allowing temperatures here to finally get back into the 40s Thursday and Friday.