Australian Government

Bureau of Meteorology


Coastal Waters Forecast 

Marine (lite) Home

IDD11030

Australian Government Bureau of Meteorology
Northern Territory

Coastal Waters Forecast for the Northern Territory

Issued at 2:30 am CST on Sunday 18 January 2026
for the period until midnight CST Tuesday 20 January 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 tropical low is forecast to develop over the Top End and deepen within a monsoon trough during the weekend. The low is expected to move towards the west and then offshore into the Timor Sea early next week. Strong winds are expected across northern and western waters over the weekend and early next week.

Beagle Bonaparte Coast: WA-NT Border to Cape Fourcroy

Forecast for Sunday 18 January until midnight

Strong Wind Warning for Sunday for Beagle Bonaparte Coast

Winds: Northwest to southwesterly 10 to 15 knots, reaching up to 30 knots offshore north of Channel Point during the morning. Seas: 1 to 2 metres, decreasing to 1 metre during the afternoon. Swell: Westerly around 1 metre inshore, increasing to 1.5 to 2 metres offshore north of Channel Point. Weather: Cloudy. 90% chance of rain. A thunderstorm likely.

Forecast for Monday 19 January

Strong Wind Warning for Monday for Beagle Bonaparte Coast

Winds: Northwest to southwesterly 10 to 15 knots, reaching up to 30 knots offshore north of Channel Point during the morning. Winds tending northwest to northeasterly before dawn. Seas: 1 to 2 metres, decreasing below 1.5 metres during the afternoon. 1st Swell: Westerly 2 to 3 metres, increasing to 2 to 4 metres during the afternoon. 2nd Swell: Northwest to northeasterly below 1 metre inshore, increasing to 1 to 1.5 metres offshore south of Channel Point later in the evening. Weather: Cloudy. 80% chance of rain. The chance of a thunderstorm.

Forecast for Tuesday 20 January

Winds: Northwesterly 10 to 15 knots. Seas: Around 1 metre. Swell: Westerly 2 to 3 metres inshore, increasing to 2.5 to 4 metres offshore north of Channel Point. Weather: Partly cloudy. 80% chance of showers. The chance of a thunderstorm.

North Tiwi Coast: Cape Fourcroy to Cape Don

Forecast for Sunday 18 January until midnight

Strong Wind Warning for Sunday for North Tiwi Coast

Winds: Westerly 15 to 20 knots, reaching up to 30 knots offshore during the morning. Seas: 1 to 1.5 metres, increasing to 1.5 to 2.5 metres offshore. Swell: Westerly 1 to 1.5 metres inshore, increasing to 1.5 to 2.5 metres offshore. Weather: Cloudy. 90% chance of rain. The chance of a thunderstorm.

Forecast for Monday 19 January

Strong Wind Warning for Monday for North Tiwi Coast

Winds: Northwesterly 15 to 20 knots, reaching up to 30 knots offshore during the day. Seas: 1 to 1.5 metres, increasing to 1.5 to 2.5 metres during the morning. Swell: Westerly 1 to 1.5 metres inshore, increasing to 2 to 3 metres offshore. Weather: Cloudy. 90% chance of rain. The chance of a thunderstorm in the morning and afternoon.

Forecast for Tuesday 20 January

Winds: Northwesterly 15 to 20 knots. Seas: 1 to 1.5 metres, decreasing to 1 metre during the morning. Swell: Westerly 1 to 1.5 metres inshore, increasing to 2 to 3 metres offshore. Weather: Partly cloudy. 80% chance of showers. The chance of a thunderstorm in the morning and afternoon.

Van Diemen Gulf

Forecast for Sunday 18 January until midnight

Winds: Northwesterly 15 to 20 knots. Seas: 1 to 1.5 metres. Swell: North to northwesterly below 1 metre. Weather: Cloudy. 80% chance of rain. The chance of a thunderstorm.

Forecast for Monday 19 January

Winds: Northwesterly 15 to 20 knots. Seas: Around 1 metre, increasing to 1 to 1.5 metres inshore around midday. Swell: North to northwesterly below 1 metre. Weather: Cloudy. 80% chance of rain. A thunderstorm likely.

Forecast for Tuesday 20 January

Winds: Northwesterly 10 to 15 knots turning westerly during the evening. Seas: Below 1 metre. Swell: North to northwesterly below 1 metre. Weather: Partly cloudy. 80% chance of showers. A thunderstorm likely.

Arafura Coast: Cape Don to Cape Wessel

Forecast for Sunday 18 January until midnight

Strong Wind Warning for Sunday for Arafura Coast

Winds: Northwesterly 15 to 20 knots, reaching up to 30 knots offshore west of Maningrida in the afternoon. Seas: 1 to 1.5 metres, increasing to 1 to 2 metres offshore west of Maningrida. Swell: Northwesterly 1 to 1.5 metres, increasing to 1.5 to 2 metres around midday. Weather: Partly cloudy. 70% chance of showers. The chance of a thunderstorm.

Forecast for Monday 19 January

Winds: Northwesterly 15 to 20 knots, reaching up to 25 knots in the far north in the late afternoon. Seas: 1 to 1.5 metres, increasing to 1 to 2 metres in the far north. Swell: Northwesterly 1 to 1.5 metres inshore, increasing to 2 metres offshore. Weather: Partly cloudy. 80% chance of showers. The chance of a thunderstorm.

Forecast for Tuesday 20 January

Winds: West to northwesterly 15 to 20 knots. Seas: 1 to 1.5 metres, increasing to 1.5 to 2 metres offshore east of Maningrida. Swell: Northwesterly 1 to 1.5 metres inshore, increasing to 1.5 to 2 metres offshore. Weather: Partly cloudy. 80% chance of showers. The chance of a thunderstorm.

Gove Peninsula Coast: Cape Wessel to Cape Arnhem

Forecast for Sunday 18 January until midnight

Winds: Northwesterly 15 to 20 knots. Seas: 1 to 1.5 metres, increasing to 1 to 2 metres inshore. Swell: Northwesterly below 1 metre inshore, increasing to 1 to 1.5 metres offshore. Weather: Partly cloudy. 70% chance of showers. The chance of a thunderstorm.

Forecast for Monday 19 January

Winds: Northwesterly 15 to 25 knots. Seas: 1 to 2 metres. Swell: Northwesterly below 1 metre inshore, increasing to 1.5 to 2 metres offshore. Weather: Partly cloudy. 80% chance of showers. The chance of a thunderstorm in the morning and afternoon.

Forecast for Tuesday 20 January

Winds: Westerly 20 to 25 knots. Seas: 1.5 to 2 metres. Swell: West to northwesterly 1 to 1.5 metres offshore, decreasing to around 1 metre during the evening. Weather: Partly cloudy. 90% chance of showers. The chance of a thunderstorm in the morning and afternoon.

Roper Groote Coast: Cape Arnhem to QLD-NT Border

Forecast for Sunday 18 January until midnight

Winds: Northwesterly 10 to 15 knots, reaching up to 20 knots offshore north of Numbulwar during the morning and early afternoon. Seas: 1 to 1.5 metres, decreasing to 1 metre around midday. Swell: Northerly around 1 metre. Weather: Partly cloudy. 60% chance of showers. The chance of a thunderstorm.

Forecast for Monday 19 January

Winds: Northwesterly 10 to 15 knots, reaching up to 20 knots northeast of Groote Eylandt during the day. Seas: Below 1 metre, increasing to 1 to 1.5 metres offshore north of Numbulwar. Swell: Northerly around 1 metre. Weather: Partly cloudy. 80% chance of showers. The chance of a thunderstorm.

Forecast for Tuesday 20 January

Winds: Westerly 15 to 20 knots. Seas: Below 1 metre, increasing to 1 to 1.5 metres northeast of Groote Eylandt. Swell: North to northwesterly around 1 metre east of Groote Eylandt. Weather: Partly cloudy. 80% chance of showers. The chance of a thunderstorm.

Darwin Harbour

Forecast for Sunday 18 January until midnight

Winds: West to northwesterly 10 to 15 knots turning northerly in the early morning. Seas: Below 1 metre. Swell: Northwesterly around 1 metre. Weather: Cloudy. 90% chance of rain. A thunderstorm likely.

Forecast for Monday 19 January

Winds: Northerly 10 to 15 knots tending northwesterly in the middle of the day then decreasing to about 10 knots in the evening. Seas: Below 1 metre. Swell: Northwesterly around 1 metre, increasing to 1 to 1.5 metres during the morning. Weather: Cloudy. 80% chance of rain. A thunderstorm likely.

Forecast for Tuesday 20 January

Winds: West to northwesterly about 10 knots. Seas: Below 1 metre. Swell: Northwesterly 1 to 1.5 metres. Weather: Partly cloudy. 80% chance of showers. A thunderstorm likely.

The next routine forecast will be issued at 8:30 am CST Sunday.

* 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.