AccuWeather.com

Snow picture courtesy of Photos.com

A quick-hitting snow will will drive eastward along part of the I-80/90 corridor in the Upper Midwest tonight.

Cities on the receiving end of accumulating snow include Milwaukee, Wis., Chicago, Ill., South Bend, Ind. and Detroit, Mich.

A storm system moving along over the northern half of the nation spread snow across the Dakotas this morning.

The snow area will consolidate into a narrow and heavy west to east band, reaching northern Illinois and southern Wisconsin this afternoon and evening. Next stop for the snow will be upstate New York, northern New England and neighboring Canada late tonight, Friday and Friday night.

Precipitation will first start as a rain across eastern Iowa, northern Illinois and part of lower Michigan before turning to all snow during the evening and overnight hours as colder air wraps into the storm.

Conditions will deteriorate late tonight in Detroit and Toronto once snow begins to fall in earnest tonight and early Friday morning.

A narrow swath of snow will accumulate 3 to 6 inches from Iowa to Michigan, but some places north and west of Chicago and Detroit will see more than half a foot of heavy wet snow.

For a larger version of this map, visit the Winter Weather Center.

However, the gradient of accumulating snow will be very sharp as a span of 100 miles north or south could mean the difference between 6 inches or more of snow or less than 3 inches.

Residents who will be traveling today and tonight across the Upper Midwest should be prepared for slower travel and use extra caution when driving on snow-covered roads. Be sure to drive carefully and allow for more time to reach final destinations.

As cold air filters into the region tonight, any slushy or wet roads will freeze and create treacherous driving conditions.

The heavy wet snow will also have the potential to cause airport delays and even flight cancellations.

According to Senior Meteorologists Danny Pydynowski and Rob Miller, "Chicago O'Hare International, Detroit Metropolitan, and Toronto Pearson International airports will face flight delays and cancellations into Friday morning."

"Airports around the country who won't even see a flake of snow will be impacted by the snow in the Upper Midwest as well," Pydynowski and Miller added.

This same storm system will also be responsible for igniting severe thunderstorms across the part of the Ohio and Tennessee valleys late this afternoon and evening. The storms will be capable of damaging wind, large hail and even a few tornadoes.

Behind the potent system, colder air will push into the Plains on howling northwesterly winds. Some places will have winds gusting past 50 mph at times.

High winds have the potential to knock down trees and power lines, which can lead to power outages. The strong winds can also make travel difficult, especially for high-profile vehicles.

Looking ahead, a northern Plains snowstorm may be brewing for later this weekend with the potential for strong winds, heavy snow and blowing snow.

AccuWeather.com meteorologists will continue to monitor the potential storm. Check back often for future updates.

By Mark Miller, Meteorologist