U.S. Snowfall Calculator
Enter any U.S. ZIP code or city name to calculate upcoming snowfall accumulation, view 36-hour hourly timelines, and track active winter storm warnings.
How Official Snowfall Is Measured and Calculated
The National Weather Service uses standard 6-hour observation cycles using calibrated white snowboard surfaces placed in open areas. Liquid precipitation equivalents (quantitative precipitation forecast or QPF) are converted to snowfall using atmospheric temperature and moisture profiles—typically known as the snow-to-liquid ratio (SLR).
Occurs near freezing (30°F to 34°F). One inch of liquid water equals 10 inches of dense, heavy snow that clings to branches and causes power outages.
Typical mid-winter storm conditions (20°F to 28°F). Creates standard snowflake crystal structures and average road pack density.
Occurs during extreme arctic cold or in dry mountain terrain (Rocky Mountains / Wasatch). Light, fluffy "champagne powder" easily blown by wind.