- Awareness Month in Hawaii
- Damaging Tropical Cyclones
- History: Central Pacific (NWS), Other Regions (Unisys)
- Preparedness
- Storm Names (NOAA)
- Storm Surge
- Terminology
A hurricane is a severe tropical cyclone with sustained winds of 74 mph (64 knots) or greater. Major hazards include high winds, heavy rainfall, flooding, storm surge and high surf. Hurricane is the term used for systems located in the central and eastern Pacific regions. Systems of this intensity occurring in the western Pacific are called typhoons. Five categories for hurricanes of various intensities have been established.
The Saffir-Simpson Hurricane Scale is a 1-5 rating based on the hurricane's present intensity. This is used to give an estimate of the potential property damage and flooding expected along the coast from a hurricane landfall. Wind speed is the determining factor in the scale.
| Barometric Pressure | Wind Speed | Storm Surge | Damage Potential |
Category One (1): Weak |
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> 28.94 in
(980 mb) |
74-95 mph
(64-82 kt or 119-153 km/hr) |
4-5 ft | Minimal damage to vegetation. No real damage to other structures. Some damage to poorly constructed signs. Low-lying coastal roads inundated, minor pier damage, some small craft in exposed anchorage torn from moorings. |
Category Two (2): Moderate |
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|
28.50-28.94 in
(965-980 mb) |
96-110 mph
(83-95 kt or 154-177 km/hr) |
6-8 ft | Considerable damage to vegetation; some trees blown down. Major damage to exposed mobile homes. Moderate damage to houses. Considerable damage to piers; marinas flooded. Small craft in unprotected anchorages torn from moorings. Evacuation from some shoreline residences and low-lying areas required. |
Category Three (3): Strong |
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|
27.91-28.50 in
(945-965 mb) |
111-130 mph
(96-113 kt or 178-209 km/hr) |
9-12 ft | Large trees blown down. Mobile homes destroyed. Extensive damage to small buildings. Poorly constructed signs blown down. Serious coastal flooding; larger structures near coast damaged by battering waves and floating debris. |
Category Four (4): Very Strong |
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|
27.17-27.91 in
(920-945 mb) |
131-155 mph
(114-135 kt or 210-249 km/hr) |
13-18 ft | All signs blown down. Complete destruction of mobile homes. Extreme structural damage. Major damage to lower floors of structures due to flooding and battering by waves and floating debris. Major erosion of beaches. |
Category Five (5): Catastrophic |
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< 27.17 in
(920 mb) |
> 155 mph
(135 kt or 249 km/hr) |
> 18 ft | Catastrophic building failures. Devastating damage to roofs of buildings. Small buildings overturned or blown away. |