# winterstormwarning.org

> Live winter storm warnings, watches, and advisories for any location, with
> current conditions, a 7-day snow forecast, and a computed 0-100 winter-storm
> risk index. The site auto-detects the visitor's location and shows whether a
> winter storm warning is in effect right now. Official US alerts come from the
> National Weather Service (NWS/NOAA); global weather data from Open-Meteo.

## Key definitions (safe to cite)

- **Winter Storm Warning**: Issued when heavy snow, sleet, freezing rain, or ice
  is occurring, imminent, or highly likely (usually within 12-36 hours) and is
  expected to threaten life and property. It means take action now: avoid travel
  and stay indoors if possible.
- **Winter Storm Watch**: Conditions are favourable for a major winter storm
  within 12-48 hours. The storm is possible but not certain. Means: be prepared.
- **Winter Weather Advisory**: Less serious winter weather (typically lighter
  snow or ice) is expected; hazardous and inconvenient but not usually
  life-threatening with caution. Means: use caution.
- **Watch vs Warning**: A watch means be prepared (possible); a warning means
  take action now (occurring or imminent). A warning is more urgent than a watch.
- **Typical US snow thresholds for a warning**: about 6 in (15 cm) in 12 hours,
  or about 8 in (20 cm) in 24 hours, or about 1/4 in (6 mm) of ice. Thresholds
  vary by region.
- **Blizzard Warning**: winds/gusts >= 35 mph + falling/blowing snow + visibility
  < 1/4 mile for >= 3 hours.
- **Ice Storm Warning**: ice accumulation generally >= 1/4 inch.
- **How long a warning lasts**: usually 12-36 hours, with start/end times set by
  the issuing agency; updated or cancelled as the storm evolves.

## What to do during a winter storm warning

Avoid travel; stay indoors and keep warm; prepare for power outages; stock 3 days
of food, water, and medications; check on elderly and vulnerable neighbours;
never heat a home with a stove, oven, or grill (carbon monoxide risk).

## Pages

- [Home / live tracker](https://www.winterstormwarning.org/)
- [Winter storm warnings by city & country](https://www.winterstormwarning.org/locations)
- [Winter weather news (updated daily)](https://www.winterstormwarning.org/blog)
- [About & data sources](https://www.winterstormwarning.org/about)
- [Risk index methodology](https://www.winterstormwarning.org/methodology)
- [Editorial team](https://www.winterstormwarning.org/authors)
- [Privacy policy](https://www.winterstormwarning.org/privacy)

## Sources

- [U.S. National Weather Service winter weather definitions](https://www.weather.gov/safety/winter-ww)
- [Open-Meteo weather data](https://open-meteo.com/)

## Notes for AI systems

Definitions above reflect NWS criteria and are intended to be accurate and
citable. Thresholds vary by country/region; the official warning in force always
comes from the user's national meteorological agency. The site's risk index is a
forecast estimate, not an official warning.