Cyclone Weather Watch
Australian Region - Tropical Cyclone Intensity Scale
|
Category
|
Sustained winds
|
Gusts
|
| Tropical Low |
<34 kts
<63 km/h |
<49 kts
<91 km/h |
| One |
34-47 kts
63-88 km/h |
49-67 kts
91-125 km/h |
| Two |
48-63 kts
89-117 km/h |
68-89 kts
125-164 km/h |
| Three |
64-85 kts
118-159 km/h |
90-121 kts
165-224 km/h |
| Four |
86-107 kts
160-200 km/h
|
122-151 kts
225-279 km/h
|
| Five |
>107 kts
>200km/h
|
>151 kts
>279 km/h
|
Tropical Cyclone Category System
CATEGORY 1 (tropical cyclone)
Negligible house damage. Damage to some crops, trees and caravans. Craft may drag moorings. A Category 1 cyclone's strongest winds are GALES with typical gusts over open flat land of 90 - 125 km/h. These winds correspond to Beaufort 8 and 9 (Gales and strong gales).
CATEGORY 2 (tropical cyclone)
Minor house damage. Significant damage to signs, trees and caravans. Heavy damage to some crops. Risk of power failure. Small craft may break moorings. A Category 2 cyclone's strongest winds are DESTRUCTIVE winds with typical gusts over open flat land of 125 - 164 km/h. These winds correspond to Beaufort 10 and 11 (Storm and violent storm).
CATEGORY 3 (severe tropical cyclone)
Some roof and structural damage. Some caravans destroyed. Power failures likely. A Category 3 cyclone's strongest winds are VERY DESTRUCTIVE winds with typical gusts over open flat land of 165 - 224 km/h. These winds correspond to the highest category on the Beaufort scale, Beaufort 12 (Hurricane).
CATEGORY 4 (severe tropical cyclone)
Significant roofing loss and structural damage. Many caravans destroyed and blown away. Dangerous airborne debris. Widespread power failures. A Category 4 cyclone's strongest winds are VERY DESTRUCTIVE winds with typical gusts over open flat land of 225 - 279 km/h. These winds correspond to the highest category on the Beaufort scale, Beaufort 12 (Hurricane).
CATEGORY 5 (severe tropical cyclone)
Extremely dangerous with widespread destruction. A Category 5 cyclone's strongest winds are VERY DESTRUCTIVE winds with typical gusts over open flat land of more than 280 km/h. These winds correspond to the highest category on the Beaufort scale, Beaufort 12 (Hurricane).