Meteorology: Understanding the Atmosphere            Ackerman and Knox

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The Saffir-Simpson scale for hurricanes, named for the engineer and the meteorologist who devised it in the 1970s. Adapted from information provided by Dr. Chris Landsea, Atlantic Oceanographic and Meteorological Laboratory.

Saffir-Simpson Scale

Saffir-Simpson
Category

Maximum sustained wind speed

Minimum surface pressure

Storm surge

mph

m/s

kts

mb

ft

m

1

74-95

33-42

64-82

greater than 980

3-5

1.0-1.7

2

96-110

43-49

83-95

979-965

6-8

1.8-2.6

3

111-130

50-58

96-113

964-945

9-12

2.7-3.8

4

131-155

59-69

114-135

944-920

13-18

3.9-5.6

5

156+

70+

136+

less than 920

19+

5.7+

 

 

Damage

Category

Level

Description

Example

1

MINIMAL

Damage primarily to shrubbery, trees, foliage, and unanchored homes. 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.

Hurricane Agnes (1972)

2

MODERATE

Considerable damage to shrubbery and tree foliage; some trees blown down. Major damage to exposed mobile homes. Extensive damage to poorly constructed signs. Some damage to roofing materials of buildings; some window and door damage. No major damage to buildings. Coast roads and low-lying escape routes inland cut by rising water 2 to 4 hours before arrival of hurricane center. Considerable damage to piers. Marinas flooded. Small craft in unprotected anchorages torn from moorings. Evacuation of some shoreline residences and low-lying areas required.

Hurricane Georges (1998)

3

EXTENSIVE

Foliage torn from trees; large trees blown down. Practically all poorly constructed signs blown down. Some damage to roofing materials of buildings; some wind and door damage. Some structural damage to small buildings. Mobile homes destroyed. Serious flooding at coast and many smaller structures near coast destroyed; larger structures near coast damaged by battering waves and floating debris. Low-lying escape routes inland cut by rising water 3 to 5 hours before hurricane center arrives. Flat terrain 5 feet of less above sea level flooded inland 8 miles or more. Evacuation of low- lying residences within several blocks of shoreline possibly required.

Hurricane Celia (1970)

4

EXTREME

Shrubs and trees blown down; all signs down. Extensive damage to roofing materials, windows and doors. Complete failures of roofs on many small residences. Complete destruction of mobile homes. Flat terrain 10 feet of less above sea level flooded inland as far as 6 miles. Major damage to lower floors of structures near shore due to flooding and battering by waves and floating debris. Low-lying escape routes inland cut by rising water 3 to 5 hours before hurricane center arrives. Major erosion of beaches. Massive evacuation of all residences within 500 yards of shore possibly required, and of single- story residences within 2 miles of shore.

Hurricane Andrew (1992)

5

CATASTROPHIC

Shrubs and trees blown down; considerable damage to roofs of buildings; all signs down. Very severe and extensive damage to windows and doors. Complete failure of roofs on many residences and industrial buildings. Extensive shattering of glass in windows and doors. Some complete building failures. Small buildings overturned or blown away. Complete destruction of mobile homes. Major damage to lower floors of all structures less than 15 feet above sea level within 500 yards of shore. Low-lying escape routes inland cut by rising water 3 to 5 hours before hurricane center arrives. Massive evacuation of residential areas on low ground within 5 to 10 miles of shore possibly required.

Hurricane Camille (1969)

 

The Hurricane Category can be estimated based on satellite images.    The table below gives examples of how different category hurricanes appear in infrared satellite images

 
Hurricane Intensity

click thumbnail to view remotely sensed image

Tropical Depression (Pre-Storm)

 

Tropical StormCategory 1Category 2Category 3Category 4Category 5