ROCKFORD (WREX) — 4 out of the first 5 days this December have been above average and in the 40's. Some changes are on the horizon that may get rid of the milder air.
The first change comes in the form of a cold front heading into the Stateline. We'll see the front move through overnight, so the colder air won't have an effect on our temperatures until Friday. Overnight, lows hover around 30 degrees under a partly cloudy sky.
The colder air will be fully felt Friday. Despite seeing a lot of sunshine, temperatures will only warm into the middle 30's. In fact, we may see a 10 degree difference between Thursday and Friday. This kind of cool weather is right on average, however. We may not see below average weather until next week.
After Friday's cool down, the weather rebounds right away. Temperatures will be back into the middle 40's both Saturday and Sunday. Saturday keeps the sunny sky around, then cloudy weather will be overhead Sunday. There will be a slight chance for rain on Sunday.
The next change is coming early next week. A blast of Arctic air is heading our way, and will cause temperatures to plunge a lot starting Tuesday. As the cold air approaches, a chance for rain and snow breaks out around the Midwest. We may see rain as early as Sunday, as mentioned above, but most likely the rain arrives Monday. A transition over to snow is possible Monday night through Tuesday as the weather cools off. For now, snow amounts look to stay light.
The cold air is in place by Tuesday, as temperatures will drop to the 20's for highs. We'll keep cooling off from there, with the single digits coming Tuesday night. There's a chance for subzero wind chills Tuesday night. Wednesday looks to be the worst of the cold, as highs may not warm above the teens. Wind chills will be near zero for much of the day.
The Arctic outbreak may be short-lived, as temperatures rebound back to the 20's on Thursday and keep warming from there.