Australian Government

Bureau of Meteorology


Coastal Waters Forecast 

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IDS11072

Australian Government Bureau of Meteorology
South Australia

Coastal Waters Forecast for South Australia

Issued at 3:30 pm CST on Monday 20 July 2026
for the period until midnight CST Thursday 23 July 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.

Warning Information

For latest warnings go to www.bom.gov.au, subscribe to RSS feeds, call 1300 659 210* or listen for warnings on relevant TV and radio broadcasts.

Weather Situation

A high pressure system over Victoria extends a ridge over South Australia, with the ridge expected to weaken during Tuesday. A trough will develop in the west on Tuesday, ahead of a weak cold front that is expected to extend over southern parts during Wednesday. Another ridge will extend over the west of the state later Wednesday, with a high centre expected to build over the Bight Thursday and Friday.

Far West Coast: WA-SA Border to Fowlers Bay

Forecast for Monday 20 July until midnight

Winds: Variable about 10 knots. Seas: Below 1 metre. Swell: Southwesterly 2 metres. Weather: Cloudy.

Forecast for Tuesday 21 July

Winds: Variable about 10 knots becoming south to southwesterly 10 to 15 knots in the morning. Seas: Around 1 metre. Swell: Southwesterly 1.5 to 2 metres. Weather: Partly cloudy.

Forecast for Wednesday 22 July

Winds: Southwesterly 15 to 20 knots turning southerly 10 to 15 knots during the day. Seas: Around 1 metre. Swell: Southwesterly 1.5 to 2.5 metres. Weather: Partly cloudy. 70% chance of showers.

Forecast for Thursday 23 July

Winds: Southerly 10 to 15 knots turning southeasterly during the evening. Seas: Around 1 metre. Swell: Southwesterly 2.5 to 3 metres inshore, increasing to 2.5 to 4 metres offshore. Weather: Partly cloudy. 60% chance of showers.

Upper West Coast: Fowlers Bay to Elliston

Forecast for Monday 20 July until midnight

Winds: North to northeasterly about 10 knots. Seas: Below 1 metre. Swell: Southwesterly 2 to 2.5 metres. Weather: Cloudy.

Forecast for Tuesday 21 July

Winds: Northwest to northeasterly 10 to 15 knots tending northwest to southwesterly in the early afternoon then tending southwesterly in the late evening. Seas: Below 1 metre. Swell: Southwesterly 2 to 2.5 metres. Weather: Cloudy.

Forecast for Wednesday 22 July

Winds: Southwesterly 10 to 15 knots turning southerly during the afternoon and evening. Seas: Around 1 metre. Swell: Southwesterly 1.5 to 2.5 metres. Weather: Partly cloudy. 80% chance of showers.

Forecast for Thursday 23 July

Winds: Southerly 10 to 15 knots decreasing to about 10 knots during the evening. Seas: Around 1 metre. Swell: Southwesterly 2.5 to 3 metres, increasing to 3 to 4 metres during the afternoon. Weather: Partly cloudy. 60% chance of showers.

Lower West Coast: Elliston to Cape Carnot

Forecast for Monday 20 July until midnight

Winds: Northerly 10 to 15 knots decreasing to about 10 knots in the evening. Seas: Around 1 metre. Swell: Southwesterly 2 to 2.5 metres. Weather: Cloudy.

Forecast for Tuesday 21 July

Winds: Northerly 10 to 15 knots shifting west to southwesterly in the late afternoon. Seas: Below 1 metre. Swell: Southwesterly 2 to 2.5 metres. Weather: Cloudy. 60% chance of showers.

Forecast for Wednesday 22 July

Winds: West to southwesterly 15 to 20 knots tending south to southwesterly 10 to 15 knots during the day. Seas: Around 1 metre, increasing to 1 to 1.5 metres during the morning. Swell: Southwesterly 2 metres, increasing to 2 to 3 metres during the morning. Weather: Partly cloudy. 90% chance of showers.

Forecast for Thursday 23 July

Winds: Southerly 10 to 15 knots. Seas: Around 1 metre. Swell: Southwesterly 3 metres, increasing to 3 to 4 metres during the morning. Weather: Partly cloudy. 60% chance of showers.

Central Coast

Forecast for Monday 20 July until midnight

Winds: North to northwesterly 10 to 15 knots decreasing to about 10 knots in the evening. Seas: Around 1 metre. Swell: Southwesterly 2.5 metres. Weather: Cloudy.

Forecast for Tuesday 21 July

Winds: Northerly 10 to 15 knots turning westerly in the late morning and afternoon. Seas: Below 1 metre. Swell: Southwesterly 2 to 2.5 metres. Weather: Cloudy. 80% chance of showers.

Forecast for Wednesday 22 July

Winds: Westerly 15 to 20 knots turning southwesterly early in the morning. Seas: Around 1 metre, increasing to 1 to 1.5 metres during the morning. Swell: Southwesterly 2 metres, increasing to 2 to 3 metres during the morning. Weather: Partly cloudy. 90% chance of showers.

Forecast for Thursday 23 July

Winds: Southwesterly 15 to 20 knots. Seas: Around 1 metre. Swell: Southwesterly 3 to 4 metres. Weather: Cloudy. 60% chance of showers.

South Central Coast

Forecast for Monday 20 July until midnight

Winds: North to northwesterly 10 to 15 knots. Seas: Around 1 metre. Swell: Southwesterly 2 to 3 metres. Weather: Cloudy.

Forecast for Tuesday 21 July

Winds: North to northwesterly 10 to 15 knots tending west to northwesterly 15 to 20 knots in the late morning and afternoon. Seas: Around 1 metre. Swell: Southwesterly 2 to 3 metres, decreasing to 2 metres later in the evening. Weather: Cloudy. 80% chance of showers. The chance of a thunderstorm in the afternoon and evening.

Forecast for Wednesday 22 July

Winds: Westerly 15 to 20 knots turning southwesterly in the early morning. Seas: 1 to 1.5 metres. Swell: Southwesterly 2 to 2.5 metres, increasing to 2.5 to 4 metres during the afternoon. Weather: Partly cloudy. 95% chance of showers, with possible small hail in the evening.

Forecast for Thursday 23 July

Winds: Southwesterly 15 to 20 knots. Seas: 1 to 1.5 metres. Swell: Southwesterly 3 to 4 metres. Weather: Cloudy. 70% chance of showers, with possible small hail in the morning.

Upper South East Coast: Murray Mouth to Cape Jaffa

Forecast for Monday 20 July until midnight

Winds: Northerly 10 to 15 knots decreasing to about 10 knots in the late evening. Seas: Around 1 metre. Swell: Southwesterly 2 to 2.5 metres. Weather: Cloudy.

Forecast for Tuesday 21 July

Winds: Northerly 10 to 15 knots turning northwesterly in the early afternoon. Winds reaching up to 20 knots offshore in the late evening. Seas: Below 1 metre. Swell: Southwesterly 2 to 2.5 metres. Weather: Cloudy. 50% chance of showers. The chance of a thunderstorm offshore in the afternoon and evening.

Forecast for Wednesday 22 July

Winds: West to northwesterly 15 to 20 knots tending west to southwesterly early in the morning. Seas: 1 to 1.5 metres. Swell: Southwesterly 2 metres, increasing to 2 to 3 metres around midday. Weather: Partly cloudy. 95% chance of showers, with possible small hail in the evening.

Forecast for Thursday 23 July

Winds: Southwesterly 15 to 20 knots. Seas: 1 to 1.5 metres. Swell: Southwesterly 2.5 to 3 metres, increasing to 3 to 4 metres during the morning. Weather: Partly cloudy. 80% chance of showers, with possible small hail in the morning and afternoon.

Lower South East Coast: Cape Jaffa to SA-VIC Border

Forecast for Monday 20 July until midnight

Winds: North to northwesterly 10 to 15 knots, reaching up to 20 knots south of Port MacDonnell during the afternoon and evening. Seas: Around 1 metre, increasing to 1 to 1.5 metres south of Beachport. Swell: Southwesterly 2 to 2.5 metres. Weather: Cloudy.

Forecast for Tuesday 21 July

Winds: North to northwesterly 15 to 20 knots tending west to northwesterly during the afternoon and evening. Seas: Around 1 metre, increasing to 1 to 1.5 metres south of Beachport. Swell: Westerly 2.5 to 3 metres, tending southwesterly 2 to 2.5 metres during the morning, then tending westerly 2 to 2.5 metres later in the evening. Weather: Cloudy. 90% chance of showers. The chance of a thunderstorm offshore in the afternoon and evening.

Forecast for Wednesday 22 July

Winds: West to northwesterly 15 to 20 knots tending west to southwesterly 20 to 25 knots during the morning. Seas: 1 to 1.5 metres, increasing to 1.5 to 2 metres south of Port MacDonnell during the morning. Swell: Westerly 2 to 2.5 metres, tending southwesterly 2 to 3 metres during the morning. Weather: Partly cloudy. 95% chance of showers, with possible small hail in the afternoon and evening.

Forecast for Thursday 23 July

Winds: Southwesterly 20 to 30 knots. Seas: 1.5 metres, increasing to 1.5 to 2.5 metres south of Beachport. Swell: Southwesterly 3 to 5 metres. Weather: Cloudy. 90% chance of showers, with possible small hail in the morning and afternoon.

Spencer Gulf

Forecast for Monday 20 July until midnight

Winds: North to northeasterly about 10 knots. Seas: Below 1 metre. Swell: South to southwesterly around 1 metre south of Cowell to Wallaroo. Weather: Partly cloudy.

Forecast for Tuesday 21 July

Winds: Northerly 10 to 15 knots turning west to northwesterly during the afternoon and evening. Seas: Below 1 metre. Swell: South to southwesterly below 1 metre, increasing to 1 to 1.5 metres south of Port Neill to Port Victoria. Weather: Partly cloudy.

Forecast for Wednesday 22 July

Winds: Westerly 10 to 15 knots turning southwesterly in the late morning. Seas: Around 1 metre. Swell: South to southwesterly below 1 metre, increasing to 1 to 1.5 metres south of Cowell to Wallaroo during the afternoon. Weather: Partly cloudy. 70% chance of showers.

Forecast for Thursday 23 July

Winds: Southwesterly 10 to 15 knots turning southerly during the day. Seas: Around 1 metre. Swell: South to southwesterly 1 to 1.5 metres, increasing to 1.5 to 2.5 metres during the morning. Weather: Partly cloudy. 60% chance of showers.

Gulf St Vincent

Forecast for Monday 20 July until midnight

Winds: North to northeasterly below 10 knots. Seas: Below 1 metre. Swell: South to southwesterly below 1 metre. Weather: Partly cloudy.

Forecast for Tuesday 21 July

Winds: North to northwesterly about 10 knots. Seas: Below 1 metre. Swell: South to southwesterly below 1 metre. Weather: Partly cloudy.

Forecast for Wednesday 22 July

Winds: Northwesterly 10 to 15 knots turning southwesterly in the middle of the day. Seas: Around 1 metre. Swell: South to southwesterly below 0.5 metres. Weather: Partly cloudy. 90% chance of showers.

Forecast for Thursday 23 July

Winds: Southwesterly 10 to 15 knots. Seas: Below 1 metre. Swell: Southeast to southwesterly below 0.5 metres. Weather: Partly cloudy. 60% chance of showers.

Investigator Strait

Forecast for Monday 20 July until midnight

Winds: Northerly about 10 knots. Seas: Below 1 metre. Swell: West to southwesterly 1 to 1.5 metres. Weather: Cloudy.

Forecast for Tuesday 21 July

Winds: Northerly 10 to 15 knots turning west to northwesterly during the afternoon and evening. Seas: Below 1 metre. Swell: West to southwesterly 1 to 1.5 metres, decreasing to around 1 metre later in the evening. Weather: Cloudy. 60% chance of showers.

Forecast for Wednesday 22 July

Winds: Westerly 15 to 20 knots turning southwesterly during the morning. Seas: Around 1 metre, increasing to 1 to 1.5 metres during the morning. Swell: West to southwesterly around 1 metre, increasing to 1 to 1.5 metres around midday. Weather: Partly cloudy. 90% chance of showers.

Forecast for Thursday 23 July

Winds: Southwesterly 10 to 15 knots. Seas: Around 1 metre. Swell: West to southwesterly 1 to 1.5 metres. Weather: Partly cloudy. 50% chance of showers.

The next routine forecast will be issued at 9:30 pm CST Monday.

* 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.