About Snowday
What is Snowday? It is an independent, free snow day calculator at willitsnowday.com that estimates the chance a US school closes tomorrow — one number, 0–100%, built from live Open-Meteo forecast data and published weights. It has no accounts and no paywall; the trade-off is honesty: a smart guess, not a guarantee.
What this site is
The bottom line: one tool, one methodology page, and a set of state guides — with every factual claim sourced or clearly labeled as an estimate.
Snowday is a free snow day calculator that estimates the chance a US school closes for snow tomorrow from live Open-Meteo forecast data. The calculator runs entirely in your browser: your location text goes to the free Open-Meteo geocoding and forecast APIs and nothing else — there is no Snowday server, database, or account system to leak.
Around the tool you will find an honest methodology page, statistics and forecast-reading guides, and 20 state guides covering local closure norms. Where we state numbers — average snowfall, storm totals, closure norms — we either name the source (NOAA/NCEI climate normals, NWS reports) or label the figure as a general estimate.
Why it stays free
The bottom line: the weather data is public, the compute is your own browser, and the only cost left is hosting — so the tool costs nothing to use.
Open-Meteo publishes free weather APIs under a Creative Commons license, which makes the whole project possible. We may add unobtrusive display ads in reserved page slots someday to cover hosting; they will never sit inside the tool form or its results. No accounts, no premium tier, no email capture — that is the deal.
How we stay honest
The bottom line: no accuracy claims we cannot support, a hard 97% ceiling on predictions, and the formula published in full.
Every winter-weather site is tempted to shout percentages. We cap the score below 100 on purpose, we document every weight the formula uses, and our disclaimers are repeated on the tool itself: fun estimate only — always follow your school district’s official announcements.
Last updated: October 2026