Head spinning forecast

Okay,hold on to your hats! December-like temperatures today with highs in the lower 30s. Almost unbelievable when you realize that normal highs for the time of year are in the upper 40s. The good news today is that the lake effect snow machine will shut off. Plain and simple here: Lake effect snow is caused by cold winds along a warm lake. November is a prime time for this to happen as the lake is still very warm and of course we get cold enough temperatures. Let's delve into the models a little here.
This is the 850 mb chart for Thursday at 7am. It shows more cold air to our north as we see -14 Celsius line across northwestern Indiana.
Here is the 7am Friday picture. That -14 Celsius line is across the entire Great Lakes region. So temperatures will be similar to what they are this morning. The lake effect snow machine will turn on again today as well.

Now let's zip ahead to Monday at 7am. 850 mb temperatures are +8 Celsius! There is also a southern low across the area which means rain and mild temperatures. So much for a mild winter eh! But just take a glance to the north. The cold air is not too far away.