Tropical Cyclones: Plotting Information

Tropical Cyclones
[Index]

Bureau of Meteorology (BoM) Data

Cyclones are generally only included if the track commenced or moved into the Australian tropical cyclone warning areas (between 90 and 160 degrees East).

A listing of BoM data is available and includes all cyclones from 1907 to June 2005. Historical data is reviewed once updated best track data becomes available.

Joint Typhoon Warning Center (JTWC) Data

Australian Region: 90E to 180E (this is a best fit region and not an official TC basin)
South Indian Ocean (SIO): 15E to 135E
South Pacific Ocean (SPAC): 135E to 110W

A listing of JTWC data is available and includes all cyclones from 1945 to June 2004.

Southern Hemisphere Tropical Cyclone Warning Centres

The following maps from the World Meteorological Organization show the official warning centres of the Southern Hemisphere.

TCWC-Port Moresby/Papua New Guinea
TCWC-Brisbane/Australia
TCWC-Darwin/Australia
TCWC-Perth/Australia
RSMC Nadi-Tropical Cyclone Centre/Fiji
TCWC-Wellington/New Zealand
La Reunion-Tropical Cyclone Centre/Meteo-France

Tropical Cyclone Map Information

The plotting software (U.S based) displays this key on all maps. The term "Typhoon/Hurricane" should read "Tropical Cyclone". The dates on individual TC track maps are mm/dd format. The Southern Hemisphere Tropical Cyclone classification system is defined in the table below. The Hurricane and Typhoon classification systems are different.

Storm Type Pressure (mb) Max Gust (km/h) 10-min Ave Gust (km/h) Dvorak Rating Effects during landfall
Tropical Depression >= 1000
< 52 2.0

Tropical Storm 996 - 999
52 - 62 2.5

Category 1 Tropical Cyclone 986 - 995 < 125 63 - 90 3.0 - 3.5 Negligible house damage. Damage to some crops, trees and caravans.
Category 2 Tropical Cyclone 971 - 985 125 - 169 90 - 125 4.0 - 4.5 Minor house damage. Significant damage to signs, trees and caravans. Heavy damage to some crops. Risk of power failure. Small craft may break moorings.
Category 3 Tropical Cyclone 956 - 970 170 - 224 125 - 165 5.0 - 5.5 Some roof and structural damage. Some caravans destroyed. Power failures likely.
Category 4 Tropical Cyclone 930 - 955 225 - 279 165 - 225 6.0 - 7.0 Significant roofing loss and structural damage. Many caravans destroyed and blown away. Dangerous airbourne debris. Widespread power failures.
Category 5 Tropical Cyclone <= 929 > 280 > 225 7.5 - 8.0 Extremely dangerous with widespread destruction.

These definitions are from the Southern Hemisphere classification system (as used by the Australian BoM), and all maps have been plotted using it. JTWC best track data has been converted from 1-minute average winds in knots, to the Southern Hemisphere standard of 10-minute average winds in knots, then converted to km/h.
The conversion used is "JTWC 1-min" * 0.87 * 1.8532

Storm Type	Pressure (mb)	Max Gust (km/h)	10-min Ave Gust (km/h)	Dvorak Rating	Effects during landfall
Tropical Depression	>= 1000		< 52	2.0
Tropical Storm	996 - 999		52 - 62	2.5
Category 1 Tropical Cyclone	986 - 995	< 125	63 - 90	3.0 - 3.5	Negligible house damage. Damage to some crops, trees and caravans.
Category 2 Tropical Cyclone	971 - 985	125 - 169	90 - 125	4.0 - 4.5	Minor house damage. Significant damage to signs, trees and caravans. Heavy damage to some crops. Risk of power failure. Small craft may break moorings.
Category 3 Tropical Cyclone	956 - 970	170 - 224	125 - 165	5.0 - 5.5	Some roof and structural damage. Some caravans destroyed. Power failures likely.
Category 4 Tropical Cyclone	930 - 955	225 - 279	165 - 225	6.0 - 7.0	Significant roofing loss and structural damage. Many caravans destroyed and blown away. Dangerous airbourne debris. Widespread power failures.
Category 5 Tropical Cyclone	<= 929	> 280	> 225	7.5 - 8.0	Extremely dangerous with widespread destruction.

Document: information.htm
Updated: 3rd May 2006

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