Official data.
Clearly presented.
Stormscope is an independent tool that brings National Hurricane Center forecasts and National Weather Service local alerts into one view. We do not create weather forecasts or evacuation instructions.
Where the data comes from
- NHC current storms feed: storm identity, classification, location and links to official products.
- NHC GIS products: forecast points, forecast track and the official uncertainty cone.
- NWS API: active warnings and watches at the representative coordinates shown on each city page.
Freshness and saved forecasts
The tracker checks for updates about every five minutes when its scheduled refresh is running. Local alerts are cached for up to two minutes. Source publication times are shown separately from alert retrieval times. Weather products can be published at different times.
If a source is unavailable, the site may show the last saved data with a warning. Advisories older than nine hours are flagged. A storm absent from the latest NHC active list is displayed as an archive. A saved forecast is not a statement about current conditions.
What the forecast cone means
The cone describes uncertainty in the forecast track of the storm center. It does not show the full extent of damaging winds, rainfall or storm surge. Being outside the cone does not mean you are safe. Read NHC’s explanation.
Understanding city pages
City alerts are queried at a representative city coordinate, not your address. They cover all active NWS hazards at that point and are not all necessarily caused by the selected storm. No returned alerts does not mean no risk.
We do not infer a city arrival time from storm speed or distance. Follow the NHC wind-arrival products and local NWS forecasts for timing guidance.
Units and forecast comparisons
Forecast wind speeds are converted from knots to miles per hour and rounded to the nearest whole number. Times in the forecast-point table follow the source labels. City alert timestamps use the city’s time zone. Advisory comparisons use the previously saved official advisory.
Questions about a forecast?
Use the official advisory and local NWS links throughout this site. Follow local emergency management for evacuation and shelter instructions. Stormscope is not affiliated with NOAA, NHC or NWS.