How cold does it have to be for schools to close in Michigan?

With dangerous wind chill temps expected across Southeast Michigan this week, some schools will need to decide if they want to stay open.

We may see another wind chill advisory in our western counties Tuesday morning. Wind chills are expected to get close to -15 degrees again.

So, how cold does it have to be for schools to close?

The rule most school districts follow is: if the wind chill is -25 or lower, schools will close.

However, many other variables can force this rule to be flexible. For example, if there's snow or ice with the wind chill.

The -25 degree benchmark is likely because of frostbite concerns. Frostbite can occur starting around -20 degrees.

So are wind chills hitting that mark this week? On Monday, yes. But most schools were already closed for MLK Day. Tuesday will be slightly warmer, but it’ll be close.

Track: Latest school closings

---> Wind chill warning active in Metro Detroit: What that means