Port Arthur Weather Forecast
- 12
- 21
Partly cloudy
- 11
- 17
Showers. Becoming windy
- 8
- 15
Shower or two. Windy
- 10
- 21
Partly cloudy
- 11
- 25
Mostly sunny
- 11
- 22
Partly cloudy
- 11
- 18
Possible shower
Today 13 Dec South East
Partly cloudy. Medium chance of showers in the far south, slight chance elsewhere. The chance of a thunderstorm this afternoon. Winds west to northwesterly 15 to 25 km/h tending southeast to southwesterly in the morning then tending northwesterly 20 to 30 km/h in the evening. Daytime maximum temperatures between 19 and 24.
South East Coastal Waters
Tasman Island to South East Cape- Wind
- Northwest to southwesterly 15 to 20 knots, reaching up to 25 knots near Cape Bruny during the morning. Winds tending east to southeasterly 10 to 15 knots in the early afternoon then tending northwest to northeasterly in the evening.
- Seas
- 1 to 2 metres, decreasing below 1 metre during the afternoon.
- 1st Swell
- Southwesterly 1.5 to 2.5 metres.
- Weather
- Partly cloudy.
- Weather Situation
- A high pressure system lies over the Tasman Sea and extends a broad ridge over Tasmania. A weak cold front is expected to cross Tasmania during Saturday, ahead of a second stronger cold front to cross early Sunday. The next high pressure system in the Bight builds a ridge over western Tasmania during Tuesday. The high is forecast to move eastwards over Tasmania by late Monday and into the Tasman Sea on Tuesday.
Port Arthur Temperature Statistics View More
December Temperature
Tasman Island (16km)
Lowest 7 December, 2025
5.4 °CAverage December
12.1 °CHighest 4 December, 2025
24.6 °C
Climate (2020–Present)
Tasman Island (16km)
Average Low 2020–2025
9.3 °CAverage 2020–2025
11.5 °CAverage High 2020–2025
14.5 °C