Saffir–Simpson Hurricane Scale

Other Scales:

RSMC Tokyo's
Tropical Cyclone Intensity Scale
Official cyclone strength scale for the Western North Pacific.

RSMC Tokyo's
Tropical Cyclone Intensity Scale
CategorySustained winds
Typhoon≥64 kt
≥118 km/h
Tropical Storm
48–63 kt
89–117 km/h
Tropical Storm34–47 kt
62–88 km/h
≤33 kt
≤61 km/h

Saffir–Simpson Hurricane Scale

Wind speedStorm surge


(≥ 250km/h)
> 5.5m








Additional classifications

The Saffir–Simpson Hurricane Scale (SSHS), or the Saffir–Simpson Hurricane Wind Scale (SSHWS), classifies hurricanes — Western Hemisphere tropical cyclones that exceed the intensities of tropical depressions and tropical storms — into five categories distinguished by the intensities of their sustained winds. To be classified as a hurricane, a tropical cyclone must have maximum sustained winds of at least 74 mph (33 m/s; 64 kn; 119 km/h) (Category 1). The highest classification in the scale, Category 5, is reserved for storms with winds exceeding 155 mph (69 m/s; 135 kn; 249 km/h).


Category one
Category 1 storms usually cause no significant structural damage; however, they can topple unanchored mobile homes, as well as uproot or snap trees. Poorly attached roof shingles or tiles can blow off.
Category 1
Sustained winds
Average central pressure:
Common structure:
Category 1 storms are often very convective and often develops a faint eye.
33–42 m/s118-153km/h 

An example of a category 1 typhoon,Typhoon Chanthu 2010


Category 2
Category 2 storms are strong enough to lift a house and inflict damage upon poorly constructed doors and windows. Vegetation, poorly constructed signs, and piers can receive considerable damage.
Category 2
Sustained winds
Average central pressure:
965 - 979hpa
Common structure:Category 2 Typhoons often do not have a classic eye,and often do not much convection around the storm(except for storms which continue intensifying.
43–49 m/s154-177km/h 

An example of a category 2 typhoon,
Typhoon Sonca 2011


Category 3
These storms can cause some structural damage to small residences and utility buildings, particularly those of wood frame or manufactured materials with minor curtain wall failures. Buildings that lack a solid foundation, such as mobile homes, are usually destroyed, and gable-end roofs are peeled off. Manufactured homes usually sustain severe and irreparable damage. Flooding near the coast destroys smaller structures, while larger structures are struck by floating debris. Additionally, terrain may be flooded well inland. Near-total to total power loss is likely for up to several weeks and water will likely also be lost.
Category 3
Sustained winds50–58 m/s178–209 km/h 
An example of a category 3 typhoon,
Typhoon Kompasu 2010

Average central pressure:



The amount of convectionaround the system is variable at this stage.Often

more orgaznied  than category 1 and 2  storms.

Category 4
Catastrophic damage will occur
Category 4 hurricanes tend to produce more extensive curtainwall failures, with some complete roof structural failure on small residences. Heavy, irreparable damage and near complete destruction of gas station canopies and other wide span overhang type structures are common

Category 4
Sustained winds:
Average central pressure:

Often shaped   like a Doughnut,and
contains a medium amount of convection.
to the center,
convection is often tightly

58–70 m/s209-251km/h 
An example of a Category 4 Typhoon, Typhoon 
Kujira 2003

Category 5
Catastrophic damage will occur
Category 5 is the highest category a tropical cyclone can obtain in the Saffir-Simpson scale. These storms cause complete roof failure on many residences and industrial buildings, and some complete building failures with small utility buildings blown over or away. Collapse of many wide-span roofs and walls, especially those with no interior supports, is common. Very heavy and irreparable damage to many wood frame structures and total destruction to mobile/manufactured homes is prevalent.Cars are sometimes lifted up in the air for a few seconds.Only a few types of structures are capable of surviving intact, and only if located at least 3 to 5 miles (5 to 8 km) inland. They include office, condominium and apartment buildings and hotels that are of solid concrete or steel frame construction, public multi-story concrete parking garages, and residences that are made of either reinforced brick or concrete/cement block and have hipped roofs with slopes of no less than 35 degrees from horizontal and no overhangs of any kind, and if the windows are either made of hurricane resistant safety glass or covered with shutters.
Category 5
Sustained winds

Common structure:
Often looking like a large  spiral with  variable amount of convection.Convection

is often tightly packed near the center.

55% of category 5 typhoons have small eyes raging from 20-40km across.Very organized.
≥ 70 m/s≥ 250 km/h 

An example of a Category 5  Super Typhoon,Typhoon Megi 2010  

Additional classifications                               

Tropical Depression
Sustained winds  
Average central pressure:
Common structure:
Often convective, 
and nor as organized as the stronger category 1s.Low level circulation center often exposed.
  0-62km/hAn example of a Tropical Depression,
Tropical Depression 24w 2011

Tropical Storm / Severe Tropical Storm
Sustained winds  
Average central pressure:
Common structure:
round, with thick, dense convection near the center.55% of Tropical Storms have a exposed center, while Larger Severe Tropical Storms often develop a ragged eye, and is more convective.
.          ...........
Severe TropicalStorm: 

An Example of a Tropical Storm,
Tropical Storm Omais 02w 2011



An Example of a Severe Tropical Storm,
Severe Tropical Storm Dianmu 2010
File:Tropical Storm Dianmu Approaching South Korea on August 10, 2010.jpg

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