Winter Storms
Where winter storms are expected to cause impacts over the next three days, the odds of heavy snow, and how much snow has actually fallen. All maps come straight from NOAA and refresh automatically.
Winter Storm Impacts
The Winter Storm Severity Index (WSSI) from NOAA’s Weather Prediction Center estimates the potential impacts of snow, ice, snow load and blowing snow on society, from Limited to Extreme. It is based on the NWS National Digital Forecast Database and updates several times a day. Blank maps mean no significant winter impacts are expected.
Snowfall Probabilities
Probabilities from WPC’s Probabilistic Winter Precipitation Forecast (PWPF), an ensemble of WPC forecasts and model guidance, for each 24-hour period (days 1–3, ending 12Z). Issued twice daily during the cold season; outside winter the maps may be blank or out of date.
Observed Snowfall
The National Snowfall Analysis (v2) combines NWS cooperative and CoCoRaHS snowfall reports with radar and model data. Updated about twice a day; values are preliminary. See also Snow Cover & Drought for snow cover and depth.