Some districts close with a clear sky. The policy is about kids standing at rural stops, diesel buses that hate extreme cold, and frostbite risk, not about inches. If your district publishes a wind-chill or air-temperature cutoff, that number beats any calculator.
How cold-weather calls usually work
- Many northern districts talk about air temperatures around minus 15 F to minus 25 F, or a similar wind-chill band. Metro Detroit administrators in 2026 still described minus 15 F as a number that gets the conversation started, not an automatic close.
- Wind turns a survivable temperature into an unsafe stop. A sheltered city corner is not a township road with a 30 mph breeze.
- Pre-K and elementary close sooner than high school. If you have mixed ages, the elementary call is the one that wrecks your morning.
Calculator vs policy
The Snow Day Calculator includes temperature and wind in the hourly fields. It cannot know that your board voted a hard cutoff last July. Enter the correct school type, then still read the district winter letter.
Cold plus ice is worse than cold plus dry snow. See ice vs snow.
What to do the night before a polar-vortex headline
- Find the district’s written cold-weather policy. Screenshot it.
- Run the calculator for the 4 to 7 AM window, not the afternoon high.
- Plan childcare as if elementary might close even if the high school stays open.
- Wait for the 5 to 7 AM official text. Announcement times.
Frequently asked questions
Will school close at minus 20 F?
Some districts yes, some no. There is no national rule. Geography and stop shelter matter as much as the thermometer.
Does a snow day calculator work on cold days with no snow?
It can flag extreme cold and wind. The official policy still wins. Use both.