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Update 1:10pm = Quad Cities NWS has also upgraded to a Blizzard Warning. Jo Daviess, Carroll, Stephenson, and Whiteside... 9pm tonight to noon Tuesday.

Update 11:50am = The Chicago branch of the NWS has upgraded the Blizzard Watch to a Blizzard Warning for Winnebago, Ogle, Lee, Boone, and McHenry County from midnight tonight through noon Tuesday.

Original Post = The main update to the snowfall forecast is that I have upped the amounts slightly for this event. I pushed them to 2-4", because of the fluffy and powdery nature of the snow I expect to fly. The hardest hit areas will be the same folks that took the brunt of the last storm. Locations within 15 miles of the Wisconsin/Illinois border should be on the high end of that spectrum. The snow event begins along the Mississippi River around noon and crosses the I-39 corridor around 3pm. The snow will quit from the clouds by midnight, but that won't be the last you hear from this storm system.

Getting an accurate measurement of tonight's snowfall is going to be quite difficult once our winds turn blustery this evening at 15-30 mph. Blowing and drifting snow will be a big problem. We are basically facing white out conditions overnight making travel treacherous.

Now that I've gotten through the analysis, I will attempt to explain the headlines from the three National Weather Service offices that cover our area.

WINTER WEATHER ADVISORIES (by county)
Jo Daviess, Stephenson, Carroll, Whiteside: Noon - 6pm
Winnebago, Ogle, Lee, Boone: Noon - midnight
McHenry: 3pm - midnight
Green, Rock: 4pm - 6am tomorrow
Walworth: 7pm - 6am tomorrow

BLIZZARD WATCH (by county)
Jo Daviess, Stephenson, Carroll, Whiteside: 6pm - Noon tomorrow
Winnebago, Ogle, Lee, Boone, McHenry: Midnight - Noon tomorrow

Confusing? Yeah, probably a little. I spoke with the Milwaukee office about why they weren't on board with the blizzard headline and this was their reply: "At this point we don't plan on a Blizzard Watch. I was briefed that it doesn't look like we'll have the winds to justify a blizzard. I didn't see strong enough winds yesterday. Of course, we will be looking it over today to be sure."

Regardless of whether the winds are strong enough to be classified as a blizzard, visibilities are going to be extremely limited overnight. Once the winds start howling this evening, they won't subside until after sunrise tomorrow. -ADAM