Second winter storm is underway, dangerous travel expected

The second significant winter storm of the week is now well underway, producing snowfall rates between 1"-2" per hour. 

Difficult travel is likely during the morning commute. as roads are to quickly become wet and slushy. On top of that, the more intense snow bands will significantly drop visibility to a half mile or less, which we are already seeing in our southernmost locales.

2"-4" is possible with the first round. We then see a small window for a break from the more intense rates between late-morning and early afternoon. It's also during this time in which we could see the rain/snow mix line lift northward into N. Illinois. 

When it came to dissecting this winter storm, that was the biggest question mark, how far north into Illinois does the rain/snow mix line end up. 

For the most part, forecast models this morning keep the 32° line near or south of I-88. This would allow precipitation to remain all snow for spots along and north of the interstate. Even if we do see a chance for a light mix into the afternoon, the expectation is for precipitation to change back to all snow by mid-afternoon. From there, snow will continue to be the main type of precipitation, this time in a drier and fluffier state thanks to rapid cooling taking place in the atmosphere.

Tagging along with the fluffier snow will be an uptick in winds, which will gust up to 35-45mph during the evening and overnight. 

That will allow blowing and drifting snow to become a major concern, which may create near-whiteout conditions over a very large swath of our viewing area. Travel Friday evening into Saturday morning will be quite dangerous, if not impossible.

It’s strongly recommended that folks stay home if at all possible. This event overall will come to a close around mid-morning Saturday, leaving behind a swath of 6"-10", with isolated higher totals possible. The threat for blowing and drifting snow as well as wind-driven snow showers continue, allowing impacts to travel to extend into Saturday afternoon. On the backside of this very dynamic storm system, a rather strong northwesterly wind will help Arctic air spill into the Great Lakes. 

To take in account for the wind chills, the National Weather Service has placed Jo-Daviess, Stephenson Carroll, and Whiteside County under a Wind Chill Watch.

This will be from Saturday evening into Tuesday morning.