How the prediction works
This calculator pulls tomorrow’s forecast for whatever city you enter — expected snowfall, the overnight low, wind gusts, and general conditions — straight from live weather data. Each of those numbers gets weighed against the patterns that typically drive school closures: heavier snowfall counts for more, colder overnight lows push the odds up further, and strong wind adds risk because of blowing snow and wind chill on top of whatever falls. The result is a single percentage that updates every time you check, based on the most current forecast available.
It’s worth being upfront about what this is and isn’t. No online calculator can see inside a superintendent’s decision — every district weighs road conditions, bus routes, and local snow-clearing capacity differently, so the same forecast can mean a closure in one town and a normal day twenty miles away. Think of the percentage here as a well-informed estimate of the weather side of that decision, not a substitute for your school’s actual announcement.
What usually makes a snow day more likely
A few patterns show up again and again in what pushes a forecast from “probably fine” to “probably closed”:
- Snowfall total. A couple of inches rarely closes anything on its own, but accumulation that keeps climbing through the morning commute changes the calculus fast — especially in places without a lot of plowing capacity.
- Temperature. Snow that falls in the low 20s or colder tends to stick to roads longer than snow falling right around freezing, which raises the risk even when the totals look similar.
- Wind. Strong wind on top of snowfall creates blowing and drifting that can make roads and bus stops hazardous even after the snow itself has stopped.
- Ice and freezing rain. Sometimes the bigger threat isn’t snow depth at all — a thin layer of ice on untreated roads can be more dangerous than several inches of powder, which is part of why this calculator also factors in freezing-rain risk separately from straight snowfall.
- Timing. A storm that peaks overnight and clears by sunrise behaves very differently than one still intensifying during the morning commute, even with identical totals.
Frequently asked questions
Is this an official school closure announcement?
No. This tool estimates the odds based on the weather forecast alone. The only official source for whether your specific school is closed is your district itself, check their website, app, or local news for the final call.
How accurate is a snow day calculator?
Short-range weather forecasts (the next day or two) are generally reliable, which is what this tool relies on. But snow forecasting still has real uncertainty, small shifts in a storm’s track or temperature can change totals significantly, and no calculator can account for a district’s specific closure policy on top of that.
Does this work outside the US?
Yes, you can enter any city in the United States or Canada, and the tool will look up the matching location and pull its forecast automatically.
How often does the forecast update?
Every time you search, the calculator pulls the latest available forecast, so checking again later in the day (especially as a storm gets closer) will usually give you a more current picture than checking the night before.
Why did my percentage change since the last time I checked?
Weather forecasts get revised as a storm gets closer and meteorologists have more data to work with — a swing of a few degrees or an inch of snow in either direction is normal and can move the percentage noticeably.
Do I need to create an account or share my location?
No. Just type in a city name — nothing is saved, and no personal information is required to use the calculator.