Hurricane Wind Scale

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What’s the difference between a Category 1 storm and a Category 5? And what exactly do those numbers mean? Hurricanes are generally measured using the Saffir-Simpson Hurricane Wind Scale, which assigns a storm a 1 to 5 rating based on its sustained wind speed. The scale can also be used to project the amount of estimated property damage a storm will cause. While hurricanes that reach Category 3 or higher are considered to be major hurricanes – with the potential for loss of life and major damage – Category 1 and 2 storms should also be taken seriously, with preventive safety measures put in place.

Category Sustained Winds Types of Damage Due to Hurricane Winds

1 74-95 mph

64-82 kt

119-153 km/h

Very dangerous winds will produce some damage: Well-constructed frame homes could have damage to roof, shingles, vinyl siding and gutters. Large branches of trees will snap and shallowly rooted trees may be toppled. Extensive damage to power lines and poles likely will result in power outages that could last a few to several days.

2 96-110 mph

83-95 kt

154-177 km/h

Extremely dangerous winds will cause extensive damage: Well-constructed frame homes could sustain major roof and siding damage. Many shallowly rooted trees will be snapped or uprooted and block numerous roads. Near-total power loss is expected, with outages that could last from several days to weeks.

3(major) 111-129 mph

96-112 kt

178-208 km/h

Devastating damage will occur: Well-built framed homes may incur major damage or removal of roof decking and gable ends. Many trees will be snapped or uprooted, blocking numerous roads. Electricity and water will be unavailable for several days to weeks after the storm passes.

4(major) 130-156 mph

113-136 kt

209-251 km/h

Catastrophic damage will occur: Well-built framed homes can sustain severe damage, with loss of most of the roof structure and/or some exterior walls. Most trees will be snapped or uprooted and power poles downed. Fallen trees and power poles will isolate residential areas. Power outages will last weeks to possibly months. Most of the area will be uninhabitable for weeks or months.

5(major) 157 mph or higher

137 kt or higher

252 km/h or higher

Catastrophic damage will occur: A high percentage of framed homes will be destroyed, with total roof failure and wall collapse. Fallen trees and power poles will isolate residential areas. Power outages will last for weeks to possibly months. Most of the area will be uninhabitable for weeks or months.