Australian Government

Bureau of Meteorology


Coastal Waters Forecast 

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IDD11030

Australian Government Bureau of Meteorology
Northern Territory

Coastal Waters Forecast for the Northern Territory

Issued at 8:30 am CST on Wednesday 20 May 2026
for the period until midnight CST Friday 22 May 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 ridge of high pressure strengthening over Central Australia is directing moderate to fresh southeasterly winds over coastal waters, persisting for most of the week.

Beagle Bonaparte Coast: WA-NT Border to Cape Fourcroy

Forecast for Wednesday 20 May until midnight

Winds: Southeasterly 15 to 20 knots, reaching up to 25 knots offshore south of Channel Point during the morning. Seas: 1 to 1.5 metres, decreasing to 1 metre by early evening. Swell: East to northeasterly below 1 metre. Weather: Partly cloudy.

Forecast for Thursday 21 May

Winds: East to southeasterly 15 to 20 knots. Seas: 1 to 1.5 metres, decreasing to 1 metre during the afternoon. Swell: East to northeasterly around 1 metre offshore. Weather: Sunny.

Forecast for Friday 22 May

Winds: Southeasterly 15 to 20 knots becoming variable about 10 knots during the day. Seas: Around 1 metre. Swell: Northeasterly below 1 metre. Weather: Sunny.

North Tiwi Coast: Cape Fourcroy to Cape Don

Forecast for Wednesday 20 May until midnight

Winds: Southeasterly 15 to 20 knots turning easterly in the late morning and early afternoon. Seas: 1 to 1.5 metres. Swell: Easterly around 1 metre. Weather: Mostly sunny.

Forecast for Thursday 21 May

Winds: East to southeasterly 15 to 20 knots. Seas: Around 1 metre, increasing to 1 to 1.5 metres offshore. Swell: East to northeasterly below 1 metre inshore, increasing to 1 to 1.5 metres offshore around midday. Weather: Partly cloudy.

Forecast for Friday 22 May

Winds: East to southeasterly 15 to 20 knots. Seas: Around 1 metre, increasing to 1 to 1.5 metres offshore. Swell: East to northeasterly around 1 metre. Weather: Mostly sunny.

Van Diemen Gulf

Forecast for Wednesday 20 May until midnight

Winds: Southeasterly 15 to 20 knots. Seas: 1 to 1.5 metres, decreasing to 1 metre during the afternoon. Swell: Below 0.5 metres. Weather: Sunny.

Forecast for Thursday 21 May

Winds: East to southeasterly 15 to 20 knots decreasing to about 10 knots in the late afternoon. Seas: 1 to 1.5 metres, decreasing below 1 metre during the afternoon. Swell: Below 0.5 metres. Weather: Sunny.

Forecast for Friday 22 May

Winds: Southeasterly 10 to 15 knots becoming variable about 10 knots during the afternoon. Seas: Around 1 metre. Swell: Below 0.5 metres. Weather: Sunny.

Arafura Coast: Cape Don to Cape Wessel

Forecast for Wednesday 20 May until midnight

Winds: Southeasterly 15 to 20 knots, reaching up to 25 knots offshore west of Maningrida during the morning. Seas: 1.5 metres, increasing to 1.5 to 2 metres offshore west of Maningrida. Swell: East to southeasterly around 1 metre. Weather: Partly cloudy. 50% chance of showers.

Forecast for Thursday 21 May

Winds: Southeasterly 15 to 20 knots. Seas: 1 to 1.5 metres, increasing to 1.5 to 2 metres in the far north. Swell: East to southeasterly around 1 metre. Weather: Partly cloudy. 50% chance of showers.

Forecast for Friday 22 May

Winds: Southeasterly 15 to 20 knots. Seas: Around 1 metre, increasing to 1 to 1.5 metres offshore. Swell: Easterly below 1 metre inshore, increasing to around 1 metre offshore. Weather: Partly cloudy. 50% chance of showers.

Gove Peninsula Coast: Cape Wessel to Cape Arnhem

Forecast for Wednesday 20 May until midnight

Winds: Southeasterly 15 to 20 knots, reaching up to 25 knots offshore south of Cape Wessel during the morning and early afternoon. Seas: 1 to 1.5 metres, increasing to 1 to 2 metres offshore south of Cape Wessel. Swell: Southeasterly around 1 metre, increasing to 1 to 1.5 metres during the afternoon, then tending south to southeasterly 1 to 1.5 metres later in the evening. Weather: Partly cloudy. 50% chance of showers.

Forecast for Thursday 21 May

Winds: East to southeasterly 15 to 20 knots, reaching up to 25 knots in the far northeast in the late evening. Seas: 1 to 1.5 metres. Swell: South to southeasterly 1 to 1.5 metres, decreasing to around 1 metre during the morning, then increasing to 1 to 1.5 metres by early evening. Weather: Partly cloudy. 70% chance of showers.

Forecast for Friday 22 May

Winds: East to southeasterly 15 to 20 knots. Seas: 1 to 1.5 metres. Swell: South to southeasterly around 1 metre. Weather: Mostly sunny. 50% chance of showers.

Roper Groote Coast: Cape Arnhem to QLD-NT Border

Forecast for Wednesday 20 May until midnight

Strong Wind Warning for Wednesday for Roper Groote Coast

Winds: Southeasterly 15 to 25 knots, reaching up to 30 knots during the morning. Seas: 1.5 to 2.5 metres. Swell: East to southeasterly around 1 metre. Weather: Partly cloudy.

Forecast for Thursday 21 May

Strong Wind Warning for Thursday for Roper Groote Coast

Winds: Southeasterly 15 to 20 knots, reaching up to 30 knots offshore south of Numbulwar during the morning. Seas: 1.5 to 2.5 metres. Swell: East to southeasterly around 1 metre. Weather: Partly cloudy.

Forecast for Friday 22 May

Winds: Southeasterly 15 to 20 knots. Seas: 1 to 1.5 metres. Swell: East to southeasterly below 1 metre. Weather: Mostly sunny.

Darwin Harbour

Forecast for Wednesday 20 May until midnight

Winds: East to southeasterly 10 to 15 knots decreasing to about 10 knots in the evening. Seas: Below 1 metre. Swell: Below 0.5 metres. Weather: Sunny.

Forecast for Thursday 21 May

Winds: East to southeasterly 10 to 15 knots decreasing to below 10 knots in the late afternoon. Seas: Below 1 metre. Swell: Below 0.5 metres. Weather: Sunny.

Forecast for Friday 22 May

Winds: Southeasterly 10 to 15 knots becoming variable about 10 knots during the morning. Seas: Below 1 metre. Swell: Below 0.5 metres. Weather: Sunny.

The next routine forecast will be issued at 2:30 pm CST Wednesday.

* Calls to 1300 number cost around 27.5c inc. 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.