Australian Government, Bureau of Meteorology

Coastal Wind Warnings Service Change

In line with international standards the Bureau will introduce the terms 'storm force' and 'hurricane force' to describe wind conditions during extreme weather events that may affect coastal waters*, for example, in major tropical cyclones in the tropics or intense low pressure systems outside the tropics.

Warnings will be issued whenever strong winds, gales, storm force or hurricane force winds are expected.

* Generally out to 60 nautical miles from the coast

Map of Coastal Waters Areas

Example wind warning

In the tropics, hurricane force winds are associated with severe tropical cyclones (Category 3 and above). An illustration of a coastal waters wind warning incorporating the new terminology follows. Wave heights can be influenced by the size and movement of the weather system, shallow waters and proximity to the coast.

WARNINGS FORECAST
(ILLUSTRATION PURPOSES ONLY)

Coastal waters wind warning
For waters between Wyndham and Kuri Bay
Issued at 5:00 am CST 31 January 2010

Synoptic situation
Severe Tropical Cyclone Xenon 952 hPa Located at
5 am CST near 12.5 S 125.2 E
Forecast at 4 pm CST 13.5S 124.6E

Hurricane force wind warning
Within 15 nautical miles of centre
Clockwise winds above 64 knots. Seas to 11 metres.

Storm force wind warning
Within 25 nautical miles of centre
Clockwise winds above 48 knots. Seas to 8 metres.

Gale warning
Within 50 nautical miles of centre
Clockwise winds above 34 knots. Seas to 5 metres.


Bureau wind warning categories

force 6

Strong wind
26 to 33 knots

Probable wave heights
around 3 to 5 metres*

force 7

Gale
34 to 47 knots

Probable wave heights
around 5 to 8 metres*

force 8
force 9

Storm force
48 to 63 knots

Probable wave heights
around 8 to 11 metres*

force 10
force 11

Hurricane force
64 knots or more
Probable wave heights
around 11 metres* or more
force 12


Images courtesy Environment Canada

*Maximum waves may be up to twice the height.

Summary of wind warnings

Old wind warning New wind warning Wind range*
Strong wind Strong wind 26 to 33 knots
Gale Gale 34 to 47 knots
Storm Storm force 48 to 63 knots
- Hurricane force 64 knots or more

One knot = one nautical mile per hour = 1.85 kilometres per hour
* Ten-minute averages

Wind warnings for coastal waters attempt to provide around a 24-hour lead time and are
normally renewed every six hours.

Please be aware wind gusts can be a further 40 per cent stronger than the average and maximum waves may be up to twice the height.

1300 telephone numbers

Bureau weather warnings are available by 1300 services and are charged at the cost of a local
call, more from mobile and public phones.

Queensland 1300 360 427
New South Wales 1300 659 218
Victoria 1300 659 217
Tasmania 1300 659 216
South Australia 1300 659 215
Western Australia 1300 659 223
Northern Territory 1300 659 214

PDF brochure version of this information (490k)

Sailboats on Port Phillip Bay, photograph by Rob Morton.

Marine & Ocean

© Australian Government 2008, Bureau of Meteorology