Hurricane Forecast Cone Explained: What It Shows and Misses

The cone follows the storm’s center

The National Hurricane Center’s forecast cone describes uncertainty in the future track of a tropical cyclone’s center. It is not a drawing of the storm’s size. The cone becomes wider farther into the forecast because location forecasts become less certain with time. The center line is a forecast track, not a guaranteed route.

Hazards can extend beyond the cone

Heavy rain, storm surge, damaging wind and dangerous surf can affect places outside the cone. A location outside the shaded area can still need protective action. Check the separate forecasts and watches or warnings for the hazards affecting your location, rather than using the cone boundary to decide whether you are safe.

Category does not describe every threat

The Saffir–Simpson category describes hurricane wind strength. It does not summarize all rainfall or coastal flooding risk. A lower-category storm can still bring dangerous water hazards. Read the rainfall and storm-surge information alongside the wind forecast and follow local evacuation instructions.

Can a weakening storm still bring inland flooding?

Yes. National Weather Service guidance explains that rainfall flooding can reach hundreds of miles inland and continue after a tropical cyclone dissipates. A change in wind category does not mean the rainfall threat has ended. Read the local flood forecast and current warnings separately from the storm category.

Which products should I check alongside the track?

Use the official track advisory together with the warnings that apply to your area. Coastal residents should check storm-surge information and local evacuation instructions; inland residents also need rainfall and flood information. Tropical cyclone rain bands can produce tornadoes away from the center. No single track graphic summarizes all these hazards. Keep the issuing agency, affected area, issue time and expiry together when saving or sharing a warning.

Compare updates with their issue times

Before sharing a forecast graphic, check its storm name, basin and issue time. A saved image can remain online after a new advisory changes the track. Use the linked National Hurricane Center products for Atlantic and eastern Pacific systems; other regions have their own responsible agencies. StormScapes links reported events to their sources so you can check the current assessment.

Keep reading

• Hurricane Advisory Times: Regular, Intermediate and Special Updates