Slow-moving storm to keep dumping snow over Midwest

A slow-moving storm already responsible for dumping more than half a foot of snow on parts of Missouri and Iowa will continue to produce fresh powder over a portion of the Midwest as it sluggishly drifts eastward into the weekend.

As snow returns to Chicago and Milwaukee and reaches Detroit, air and ground travel disruptions are likely to mount into Saturday.

The storm attached to the upper part of the atmosphere early on, becoming better organized. Rather than remaining weak and taking a swift eastward track, spreading snow over huge swath from the Plains to the Northeast, the storm matured and stalled over the Mississippi Valley late this week.

The swirl of snow near and north and west of the center of the storm is forecast to hold together, drift eastward and can enhance for a time into Saturday.

"Up to a few additional inches of snow is forecast to fall on portions of central Missouri, central and eastern Iowa, northern and western Illinois, central and southeastern Wisconsin, northern Michigan and the southeastern tip of Minnesota," AccuWeather Meteorologist Courtney Travis said.

"This will bring the storm total to between 6 and 10 inches with an AccuWeather Local StormMax of 12 inches in parts of north-central Missouri, eastern Iowa, northwestern Illinois, southern Wisconsin and part of the Upper Peninsula of Michigan," Travis said.

Forecasters expect cities such as Milwaukee and Madison, Wisc., as well as Rockford, Ill., and Davenport, Iowa, to be buried under a half a foot of snow or more from the storm as it continues to evolve.

"An advancing cold pocket of air with moisture is forecast to produce snowfall in the 1- to 3-inch range from central Illinois to northern and central Indiana and the northwestern and central parts of the Lower Peninsula of Michigan Friday night and Saturday," Travis added.

Americans who live in this zone, including in Indianapolis and South Bend, Ind.; Grand Rapids, Kalamazoo and Flint, Mich.; and Champaign, Ill.; may yet have enough snow to sweep off of their cars and shovel.

A bit more snow will fall around St. Louis for a time, with up to a few more inches of snow likely to fall on Chicago. Freezing rain or drizzle will change to snow, which will fall heavily at times, in the Windy City late Friday evening into Saturday morning. The Chicago National Weather Service Office (NWS) office warned followers on Twitter Friday that travel could become tricky during the latter part of the evening commute.

Since some of the snow will fall at night and can do so at a heavy rate when road surface temperatures lower slightly, meteorologists caution that motorists should not assume that road conditions that were wet during the day will stay that way after dark. Temperatures are forecast to dip from 2 to 8 degrees Fahrenheit, on average, across the Midwest by Saturday morning, and that can be enough to create slippery conditions.

Even though blustery conditions will develop as the storm moves along this weekend, the air is of Pacific origin and not from the Arctic. Aside from snow showers near the old center of the storm, lake-effect snowfall is likely to be minimal in the storm's wake.

Saturday night, slightly colder air with snow showers will continue to advance eastward along with the old storm center. Motorists around Detroit and Toledo, Cleveland, Columbus and Youngstown, Ohio, could encounter slippery conditions with a coating of snow possible.

By Sunday, the main focus of snow showers will retreat to the central Appalachians and around the eastern Great Lakes.

Temperatures are likely to be above average during the last few days of January and the first few days of February for the North Central states. Highs will generally average within a few degrees of freezing in the northern tier to the lower 40s over portions of the central Plains and the Ohio Valley.