Light Mix of Rain & Snow Saturday Morning, Cold Blast Arrives by Christmas

Thanks to a ridge of high pressure, skies across the Stateline cleared out during the overnight hours. This gave temperatures the opportunity to "bottom out" or rapidly drop, with most spots landing about 5° to 10° cooler than the temperatures on Thursday morning. Those who stepped out the door this morning were greeted to not only a beautiful cotton-candy sunrise, but also temperatures on either side of the 20° mark. If you still have yet to walk out the door, you'll need to make sure to grab that heavier jacket before you do. 

A weak disturbance that is tracking across the Upper Midwest and central plains early Friday is behind this morning's increase in cloud cover. Similar to what we've seen throughout much of the work week, cloud cover is expected to stick around into the afternoon. Despite mostly cloudy skies, a breeze out of the south-southeast will help temperatures climb close to the 40° mark. The thermometer may read upper 30s and low 40s, but that wind make it feel like the 20s. So it wouldn't be a bad idea to keep that extra layer with you throughout the day today.

We are now one week away from the Christmas holiday, and the Stateline does have a few opportunities in the forecast to see some snow. The only downside is, it most likely won't be enough to give us an official "white Christmas". The first chance for light precipitation comes in late Friday night into Saturday morning. Although lacking moisture, model guidance shows this weak disturbance sliding in by Saturday morning, bringing a chance for a light wintry mix. Most of the region may skid on by without seeing any precipitation. But if any snow were to fall, you would most like see that in areas along and north of Highway 20, with snow chances wrapping up by shortly after sunrise. Once precipitation chances come to an end, cloudy skies will linger into Saturday afternoon, with high temperatures in the upper 30s.

The countdown continues, as we are now 7 days away from the Christmas holiday. Although the Stateline's chances for a white Christmas remains slim, we do know that a big blast of cold air is set to arrive shortly before Santa arrives. A large dip in the jet stream will allow very cold Canadian air to spill southward into the Upper Midwest and The Great Lakes region Wednesday night into Christmas eve morning. This is set to bring the total opposite of what we experienced weather-wise last year on Christmas Day. 

I know it feels like a distant memory, but last Christmas ended up being the warmest on record for the Rockford area, as the airport observed a high of 59°. By the way model trends have looked, we won't see temperatures nearly that high this time around. As this cold Canadian air-mass filters in, highs in the low 40s Wednesday will fall into the low 20s by Christmas Eve and Christmas Day. And if you think that's cold, temperatures have the opportunity to sink down into the single-digits Christmas Eve morning. Something Rockford hasn't seen since February 21st.