IDW11130
Australian Government Bureau of Meteorology
Western Australia
Issued at 1:01 am WST on Friday 21 August 2026
for the period until midnight WST Sunday 23 August 2026.
Please be aware
Wind and wave forecasts are averages. Wind gusts can be 40 per cent stronger than the forecast, and stronger still in squalls and thunderstorms. Maximum waves can be twice the forecast height.
A weak ridge lies across southern WA. A trough will deepen down the west coast later today, moving inland later on Saturday ahead of another weak cold front reaching the lower west coast on Sunday. A new ridge will begin to develop across the west coast later Sunday and into Monday behind the trough and as the weak cold front moves east along the south coast.
Winds: Northeast to southeasterly 10 to 15 knots becoming variable about 10 knots before dawn. Seas: Below 1 metre. Swell: Southwesterly 2.5 to 3 metres. Weather: Partly cloudy. 95% chance of showers offshore south of Coral Bay, 50% chance elsewhere. The chance of a thunderstorm during this afternoon and evening.
Winds: Southwesterly below 10 knots increasing to 10 to 15 knots in the middle of the day. Seas: Below 1 metre. Swell: Southwesterly 2 to 2.5 metres. Weather: Partly cloudy.
Winds: Southerly 15 to 20 knots. Seas: Around 1 metre, increasing to 1 to 1.5 metres offshore during the afternoon or evening. Swell: Southwesterly 2 to 2.5 metres. Weather: Partly cloudy.
Winds: East to southeasterly 10 to 15 knots, reaching up to 25 knots offshore south of Denham early in the morning. Seas: 1 to 2 metres, decreasing below 1 metre around midday. Swell: Southwesterly 2 to 3 metres. Weather: Partly cloudy. 50% chance of showers. The chance of a thunderstorm offshore north of Denham during this afternoon and evening.
Winds: Southeasterly 10 to 15 knots becoming variable about 10 knots before dawn then becoming south to southwesterly 15 to 20 knots in the middle of the day. Seas: Around 1 metre, increasing to 1 to 1.5 metres south of Denham during the afternoon. Swell: Southwesterly 2 to 3 metres. Weather: Partly cloudy. 50% chance of showers.
Winds: Southerly 15 to 20 knots. Seas: Around 1 metre, increasing to 1 to 2 metres south of Denham. Swell: Southwesterly 2 to 3 metres. Weather: Partly cloudy.
Winds: Southeasterly 15 to 20 knots. Seas: 1 to 2 metres, decreasing to 1 to 1.5 metres during the morning. Swell: Southwesterly 2 to 3 metres inshore, increasing to 3 to 4 metres offshore south of Geraldton. Weather: Sunny.
Winds: East to southeasterly 15 to 20 knots becoming variable about 10 knots in the early morning then becoming southerly 15 to 20 knots in the middle of the day. Seas: 1 to 1.5 metres, decreasing below 1 metre during the morning, then increasing to 1 to 1.5 metres during the afternoon. Swell: Southwesterly 2.5 to 3 metres. Weather: Sunny morning. 50% chance of showers in the afternoon and evening. The chance of a thunderstorm inshore in the afternoon.
Winds: Southerly 15 to 20 knots. Seas: 1.5 metres, decreasing to 1 metre during the morning. Swell: Southwesterly 2 to 3 metres. Weather: Partly cloudy. 60% chance of showers.
Winds: East to southeasterly 10 to 15 knots tending south to southeasterly 15 to 20 knots in the early afternoon. Seas: Around 1 metre. Swell: Southwesterly 3 metres. Weather: Sunny.
Winds: East to southeasterly 15 to 20 knots becoming variable about 10 knots in the early morning then becoming southerly 15 to 20 knots in the early afternoon. Winds reaching up to 25 knots offshore in the late evening. Seas: 1 to 1.5 metres, decreasing below 1 metre during the morning, then increasing to 1 to 1.5 metres during the afternoon. Swell: Southwesterly 2.5 to 3 metres. Weather: Partly cloudy.
Winds: Southerly 15 to 20 knots decreasing to about 10 knots during the evening. Seas: 1 to 2 metres, decreasing to 1 metre during the morning. Swell: Southwesterly 2 to 2.5 metres. Weather: Partly cloudy. 50% chance of showers.
Winds: East to southeasterly 10 to 15 knots tending south to southeasterly in the early afternoon. Seas: Below 1 metre. Swell: Southwesterly 3 metres. Weather: Mostly sunny.
Winds: Southeasterly 10 to 15 knots turning east to northeasterly below 10 knots early in the morning then tending southerly 15 to 20 knots in the middle of the day. Seas: Around 1 metre, increasing to 1 to 1.5 metres during the afternoon. Swell: Southwesterly 2.5 to 3 metres. Weather: Partly cloudy.
Winds: Southerly 15 to 20 knots decreasing to about 10 knots during the evening. Seas: 1 to 1.5 metres, decreasing to 1 metre during the morning. Swell: Southwesterly 2 to 2.5 metres. Weather: Partly cloudy. 50% chance of showers.
Winds: East to southeasterly about 10 knots tending southerly 10 to 15 knots in the evening then tending southeasterly in the late evening. Seas: Below 1 metre. Swell: Southwesterly 2.5 to 3 metres. Weather: Partly cloudy.
Winds: Southeasterly 10 to 15 knots becoming variable about 10 knots in the early morning then becoming southerly 15 to 20 knots in the morning. Seas: Below 1 metre, increasing to 1 to 1.5 metres during the afternoon. Swell: Southwesterly 2 to 3 metres. Weather: Partly cloudy.
Winds: Southerly 10 to 15 knots decreasing to about 10 knots during the evening. Seas: 1 to 1.5 metres. Swell: Southwesterly 1 to 2 metres inshore, increasing to 2 to 3 metres offshore. Weather: Partly cloudy. 50% chance of showers.
The next routine forecast will be issued at 7:01 am WST Friday.
* Calls to 1300 numbers cost around 27.5c incl. GST, higher from mobiles or public phones. Marine forecasts are also available on VHF and HF radio. View the radio schedule on www.bom.gov.au/marine
Check the latest Coastal Waters Forecasts for information on wind, wave and weather conditions for neighbouring coastal zones