A winter storm warning, hundreds of school closings and snow emergencies are in effect in anticipation of 6-9 inches of heavy snow heading to Metro Detroit after midnight Thursday.
Snowfall is expected to continue through Friday, according to the National Weather Service.
"We've got 6-9 in the forecast for Metro Detroit, but it's looking more like it's going to be in the upper range," said Trent Frey, a meteorologist with the National Weather Service in White Lake Township. "It'll depend on how the snow event unfolds, but we're expecting a bigger band of snow to set up."
The weather service issued a winter storm warning for Washtenaw, Wayne, Lenawee and Monroe counties from 3 a.m. through midnight Friday.
Areas with a winter storm advisory include Oakland, Macomb and St. Clair counties, where snowfall totals could reach the 3-7 inch range.
The Thumb region could see 1-3 inches, the National Weather Service said.
Be prepared for a difficult Friday morning commute. "It's going to be messy," Frey said.
School closings Friday include Wayne State University, Oakland University, Auburn Hills, Plymouth-Canton Community Schools, Chippewa Valley Schools, Allen Park Public Schools, Anchor Bay School District, Avondale and Royal Oak schools. WDIV (Channel 4) lists 739 school closings or delays on Friday.
Vehicles on the streets during snow emergencies that are declared by communities must be removed or owners face tickets.
By late Thursday, cities that had declared a snow emergency included Allen Park, Taylor, Warren and Oak Park.
In addition, meteorologists say light accumulating snow is possible Saturday night into Sunday as low pressure tracks through the eastern Ohio Valley. No more than a couple of inches are expected, Frey said.
"Nothing like what we're going to see tomorrow," he said.
The snow is part of a system the Weather Channel has dubbed "Winter Storm Mateo" expected to coat the upper Midwest.
"Each winter storm has its own personality, and Mateo will be known for a quick-hitting blast of heavy snowfall over a long, narrow footprint," said Tom Niziol, the channel's winter weather expert, in a statement.
"That footprint of heavy snowfall will likely be less than 100 miles wide, but will extend over a very west to east path from the Northern Rockies through Central Plains, Midwest, Northern Ohio Valley and portions of the Great Lakes."
So far this month, 9.5 inches of snow has fallen around southeast Michigan, Frey said.
In the first eight days of February last year, the area saw only 2.2 inches of snow this time of the year, according to Frey. But he said last year was an anomaly and the area usually sees more snow than that.
The other part of the weather story over the weekend is the temperature.
Frey said the temperature will remain in the mid- to high 20s through Monday. The normal temperature for this time of year is about 33 degrees.
Friday: Snow with a high near 28 degrees and a low of 18 degrees. Five inches of snow is expected to fall during the day and another inch is possible at night.
Saturday: Cloudy with a high near 28 degrees and a low of about 20 degrees. Snow is likely after 1 p.m. with less than half an inch possible.
Sunday: Snow before 1 p.m. with an inch possible. Temperatures are expected to reach a high of about 29 degrees and a low of 13 degrees.
Monday: Sunny with a high near 28 degrees and a low of about 16 degrees.
Tuesday: Partly sunny with a high near 37 degrees and a low of about 25 degrees.
Wednesday: Partly sunny with a high near 37 degrees.
Source: National Weather Service