Cold air dominates the state the rest of this week. Precipitation will be mostly limited to later in the week, but the cold will allow for some flurries here and there up to the north. Temps will be a good 10-20 degrees below normal for this time of year. We will see our first sub-zero temperature readings overnight tonight into early tomorrow morning over parts of northern Indiana, from SR 32 northward. High pressure parks over the state tomorrow night through Thursday and that will likely be where we see the coldest air come.
On the backside of the high we can have a few flurries in NW Indiana Thursday night, and that leads to minor light snows over the northern third of the state for early Friday morning. A coating to an inch is all we will be looking at, and we see nothing farther south, with sunshine in from I-70 southward. However, this primes the pump for a quick moving clipper system for Friday night into Saturday, where we see potential for snows of 1-3 inches over 60% of the state. Generally, we see no snow for that period south of US 50. The concern here is for snows higher than that range up in northern Indiana, but we will wait to zero in on that until closer to Thursday.
Everything is done by midday Saturday, but we see a second, stronger shot of cold air coming in behind that system, with very strong north winds. This will bring potential for lake effect snow over northern third of the state for the balance of Saturday, and then over Porter, Laporte and Starke counties for Sunday. Lake effect amounts can be high, but will be very, very localized. The rest of the state is just plain cold.
Flipping the calendar into 2018 brings more cold air and light snow for January 1. A coating to an inch is likely over 60% of the state from I-70 northward, just clouds farther south. Then we could string together 4 days back to back to finish the first week of 2018 in the single digits and below zero. A brutal cold air push is coming.
In the extended window, we could be looking at another major winter storm arriving around the 6th of January, with low pressure tracking directly across the state on a path from Little Rock AR to Buffalo, NY. This track could bring significant snow. But, it is far enough out to allow for plenty of wiggle room. Behind that storm complex, cold air stays, and 2 clippers are possible, adding to the snow potential over the state. Temps remain below normal through Jan 10.