The Saffir-Simpson Scale: What Hurricane Categories Mean

When a hurricane is called "Category 3," that number comes from the Saffir-Simpson Hurricane Wind Scale — a 1-to-5 rating based on a storm's maximum sustained wind speed. Here's what each step means, and the important thing the scale leaves out.

You can watch live tropical systems on the Atlantic hurricane tracker.

The five categories

The scale rates sustained wind speed and the damage it tends to cause:

• Category 1 — 74–95 mph. Dangerous winds. Damage to roofs, siding, trees and power lines; some outages.
• Category 2 — 96–110 mph. Extremely dangerous winds. Major roof and siding damage, many trees down, near-total power loss possible for days.
• Category 3 — 111–129 mph. Devastating damage; the threshold for a "major hurricane." Well-built homes lose roof decking; power and water out for days to weeks.
• Category 4 — 130–156 mph. Catastrophic damage. Severe structural damage, most trees snapped, areas potentially uninhabitable for weeks or months.
• Category 5 — 157 mph and up. Catastrophic. A high percentage of homes destroyed; long-term isolation of affected areas.

What category doesn't tell you

Here's the catch: the Saffir-Simpson scale measures wind only. But historically, most hurricane deaths come from water — storm surge and inland flooding — not wind. A "mere" Category 1 that stalls and dumps rain, or pushes a large surge, can be far deadlier than a brief Category 4.

So treat category as one piece of the picture, not the whole threat. Always follow your national weather service for surge and flood warnings.

Watch one develop

On satellite imagery, strengthening storms grow more circular and develop a clearer eye. Track active systems on the hurricane hub, and read how to read radar for when the bands reach land.