What confidence means
Confidence reflects data completeness, agreement across forecast points, time until the school day, and weather-data freshness. High Confidence is not a guarantee of a school decision or a measured historical accuracy rate.
How accurate are the odds?
SnowDayOdds.com uses a custom forecasting model designed by a real meteorologist. It combines the latest official weather forecast with the timing and type of winter weather to estimate the chance of a Snow Day, delay, early dismissal, or Normal School.
Same inputs, same odds
The same normalized weather inputs and model version produce the same probabilities for the same forecast window. This is what deterministic means: consistency, not proof of accuracy.
Validation is still ahead
The current model has not yet been calibrated or validated against enough real-world school outcomes. No measured accuracy results are published here. Evaluation needs a representative record of saved forecasts and verified school-day outcomes.
What a probability means
A 70% chance is not a guarantee. A well-calibrated model would see Snow Days about seven times out of ten across many comparable 70% forecasts. That relationship has not yet been demonstrated for this model. Real-world evaluation should compare forecasts made before school decisions with what happened, accounting for model version, forecast lead time, and how outcomes are defined.
Schools always make the final decision.
Why forecasts can change
New weather information or a future model version can change the odds. A scheduled check alone does not mean they will change. Read the Methodology for how weather input becomes school-impact probabilities.