Snow Day Calculator

The calculator scores four key factors — expected snowfall, wind speed and temperature, school type and days used, and storm timing and ice presence — each weighted differently. These scores are summed and converted to a percentage probability. Overnight heavy snowfall with icy roads and high winds scores highest, while light afternoon flurries at a boarding school score much lower.

There's no universal threshold — it depends heavily on region, school type, and road conditions. In general, 4–6 inches of overnight snow can cause closures in areas unaccustomed to heavy snowfall, while regions in the northern Midwest or New England may stay open through 10+ inches. Ice and wind are often bigger factors than snowfall totals alone.

Yes, significantly. Urban public schools tend to close more readily due to bus routes and pedestrian safety concerns. Rural public schools often stay open because students are more accustomed to winter conditions and roads are plowed early. Private and boarding schools historically have the lowest closure rates.

Decisions about school closures are usually made by 5–6 AM. If heavy snow falls overnight or in the early morning hours before the decision window, administrators can see accumulation and road conditions firsthand. Snow that falls during or after school hours has almost no impact on next-day closure decisions.

Schools typically have a set number of built-in snow days per year. If a district has already used most of them, administrators may be reluctant to call another unless conditions are extreme — since additional cancellations require adding days at the end of the year. Conversely, early in the year with no days used, schools may be quicker to close.

Often yes. Ice-covered roads and sidewalks are far more dangerous than snowy ones, and school bus safety is a top priority for administrators. Even a relatively small amount of freezing rain can push closure probability higher than several inches of fluffy, manageable snow.

This tool provides an educational estimate based on widely recognized factors that school administrators consider. It cannot account for hyperlocal road conditions, specific district policies, or real-time weather model data. For the most reliable prediction, combine this estimate with your local news, school district alerts, and weather service forecasts.

Check your school district's official website, sign up for automated phone or email alerts from your district, and monitor local TV news or radio stations. Many districts also post closures on their social media pages. The decision is usually announced by 5–6 AM on the day in question.