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 Saturday 19 September 2026
for the period until midnight CST Monday 21 September 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 strong high pressure system (1029 hPa) over the southeast of the country is driving fresh to strong easterly winds over the coastal waters. The ridge will weaken from Sunday.

Beagle Bonaparte Coast: WA-NT Border to Cape Fourcroy

Forecast for Saturday 19 September until midnight

Winds: East to northeasterly 10 to 15 knots, reaching up to 20 knots offshore north of Channel Point during the day. Winds tending northwest to northeasterly in the evening then becoming variable about 10 knots in the late evening. Seas: Around 1 metre. Swell: Northeasterly around 1 metre. Weather: Mostly sunny.

Forecast for Sunday 20 September

Winds: Variable about 10 knots becoming east to northeasterly 10 to 15 knots before dawn then tending northwest to southwesterly in the evening. Seas: Below 1 metre. Swell: Northeasterly around 1 metre offshore. Weather: Cloud clearing.

Forecast for Monday 21 September

Winds: Variable about 10 knots becoming northwest to northeasterly 10 to 15 knots during the day then tending northwest to southwesterly during the afternoon. Seas: Below 1 metre. Swell: Westerly below 1 metre. Weather: Sunny.

North Tiwi Coast: Cape Fourcroy to Cape Don

Forecast for Saturday 19 September until midnight

Winds: Easterly 15 to 20 knots. Seas: 1 to 1.5 metres. Swell: East to northeasterly around 1 metre inshore, increasing to 1 to 2 metres offshore. Weather: Mostly sunny.

Forecast for Sunday 20 September

Winds: Easterly 15 to 20 knots. Seas: 1 to 1.5 metres, decreasing to 1 metre around midday. Swell: East to northeasterly around 1 metre inshore, increasing to 1 to 2 metres offshore. Weather: Mostly sunny.

Forecast for Monday 21 September

Winds: East to northeasterly 10 to 15 knots. Seas: Below 1 metre. Swell: East to northeasterly around 1 metre. Weather: Mostly sunny.

Van Diemen Gulf

Forecast for Saturday 19 September until midnight

Winds: Easterly 15 to 20 knots tending northeasterly in the early afternoon. Seas: Around 1 metre. Swell: Below 0.5 metres. Weather: Mostly sunny.

Forecast for Sunday 20 September

Winds: Easterly 10 to 15 knots turning north to northeasterly in the late morning and early afternoon. Seas: Around 1 metre. Swell: Below 0.5 metres. Weather: Sunny.

Forecast for Monday 21 September

Winds: Easterly 10 to 15 knots tending northwest to northeasterly during the afternoon then tending northeasterly during the evening. Seas: Below 1 metre. Swell: Below 0.5 metres. Weather: Sunny.

Arafura Coast: Cape Don to Cape Wessel

Forecast for Saturday 19 September until midnight

Winds: Easterly 15 to 20 knots, reaching up to 25 knots offshore during the morning and again in the evening. Seas: 1 to 1.5 metres, increasing to 1.5 to 2 metres offshore. Swell: Easterly around 1 metre inshore, increasing to 1 to 2 metres offshore. Weather: Mostly sunny.

Forecast for Sunday 20 September

Winds: Easterly 15 to 20 knots, reaching up to 25 knots offshore west of Maningrida early in the morning. Seas: 1 to 2 metres, decreasing to 1 to 1.5 metres during the morning. Swell: Easterly around 1 metre inshore, increasing to 1 to 1.5 metres offshore. Weather: Partly cloudy.

Forecast for Monday 21 September

Winds: Easterly 15 to 20 knots. Seas: Around 1 metre. Swell: Easterly around 1 metre. Weather: Mostly sunny.

Gove Peninsula Coast: Cape Wessel to Cape Arnhem

Forecast for Saturday 19 September until midnight

Strong Wind Warning for Saturday for Gove Peninsula Coast

Winds: East to southeasterly 15 to 25 knots, reaching up to 30 knots offshore north of Cape Wessel during the morning. Seas: 1.5 to 2.5 metres, decreasing to 1.5 metres by early evening. Swell: Easterly 1 to 1.5 metres, increasing to 1 to 2 metres inshore. Weather: Partly cloudy.

Forecast for Sunday 20 September

Winds: Easterly 15 to 20 knots, reaching up to 25 knots offshore early in the morning. Seas: 1 to 2 metres, decreasing to 1 to 1.5 metres by early evening. Swell: Easterly 1 to 1.5 metres, decreasing to around 1 metre during the morning, then increasing to 1 to 1.5 metres around midday. Weather: Mostly sunny.

Forecast for Monday 21 September

Winds: Easterly 15 to 20 knots. Seas: Around 1 metre, increasing to 1 to 1.5 metres offshore north of Cape Wessel. Swell: Easterly around 1 metre. Weather: Partly cloudy.

Roper Groote Coast: Cape Arnhem to QLD-NT Border

Forecast for Saturday 19 September until midnight

Winds: Easterly 15 to 25 knots turning southeasterly 10 to 15 knots in the evening. Seas: 1 to 1.5 metres, increasing to 1.5 to 2.5 metres east of Groote Eylandt. Swell: Easterly around 1 metre, increasing to 1 to 1.5 metres around midday, then tending east to northeasterly 1 to 2 metres during the afternoon. Weather: Mostly sunny.

Forecast for Sunday 20 September

Winds: Southeasterly 10 to 15 knots turning easterly 15 to 20 knots early in the morning. Seas: 1 to 1.5 metres, increasing to 1 to 2 metres during the morning, then decreasing to 1 metre later in the evening. Swell: Easterly 1 to 1.5 metres, decreasing below 1 metre during the morning, then increasing to 1 to 1.5 metres during the afternoon. Weather: Cloud clearing.

Forecast for Monday 21 September

Winds: Variable about 10 knots becoming east to southeasterly 10 to 15 knots during the morning then becoming variable about 10 knots during the evening. Seas: Below 1 metre. Swell: East to northeasterly around 1 metre. Weather: Sunny.

Darwin Harbour

Forecast for Saturday 19 September until midnight

Winds: Easterly 10 to 15 knots tending northeasterly 15 to 20 knots in the middle of the day. Seas: Around 1 metre. Swell: Below 0.5 metres. Weather: Mostly sunny.

Forecast for Sunday 20 September

Winds: Easterly 10 to 15 knots turning north to northeasterly in the early afternoon then becoming variable below 10 knots in the evening. Seas: Below 1 metre. Swell: Below 0.5 metres. Weather: Sunny.

Forecast for Monday 21 September

Winds: East to northeasterly below 10 knots tending north to northeasterly 10 to 15 knots during the day then becoming variable below 10 knots during the afternoon. Seas: Below 1 metre. Swell: Below 0.5 metres. Weather: Sunny.

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

* 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.