(WXYZ) - Tens of thousands of families could be affected by decisions made in the dark, pre-dawn hours Wednesday.
We're talking about snow days, of course, and the decision about whether to call one involves some things other than the weather.
As 7 First Alert meteorologist Chris Edwards found out, the journey to a decision starts early.
As early as 3:00 a.m. or 3:30 a.m., someone from the school district will start driving area roads, the same ones the buses usually take.
Each school district makes its own decision, and districts with lots of dirt roads and hilly roads can vary a lot from flat, paved ones.
Neighboring districts definitely talk to each other and take cues from each other.
In fact, a group of at least seven large Oakland County districts has a conference call at 4:30 in the morning with a private meteorologist where they all get the latest weather forecast and share information about their roadways.
After that, more phone calls are likely between other district superintendents and transportation folks. The timing of the snow or ice is critical to how safe roads can be.
According to Deborah Tremp, the Associate Superintendent of Administrative Services for Southfield schools, they want the kids in school as long as it's safe. Safety is the number one priority.
The call is made by 5:30 or 6:00 a.m. at the latest. All the "deciders" I talked to told me they don't even consider how many snow days have been called already this school year; it's just about safety.
But if they did care, the state makes every district put at least six days into their calendar when school can be cancelled before make-up days come into play.
Also, you may have noticed that parochial schools cancel more often than others. That's because they draw students from much greater distances, making the trip to school more difficult on snowy days.
CHECK TO SEE IF YOUR CHILD'S SCHOOL WILL BE CLOSED WEDNESDAY HERE: http://www.wxyz.com/subindex/weather/school_closings
Follow Chris Edwards on twitter at twitter.com/edwardswxwxyz