Boat Harbour Weather Forecast
- 18
- 30
Shower or two. Possible storm
- 20
- 28
Becoming cloudy
- 17
- 28
Possible shower
- 15
- 31
Sunny day. Late shower or two
- 15
- 23
Shower or two
- 14
- 23
Partly cloudy
- 14
- 25
Partly cloudy
Today 21 Dec Illawarra
Partly cloudy. High chance of showers, most likely in the afternoon and evening. A thunderstorm likely in the afternoon and evening, possibly severe with damaging winds, large hail and heavy rain which may lead to flash flooding. Light winds becoming northwest to northeasterly 15 to 20 km/h in the middle of the day then tending west to northwesterly 15 to 25 km/h in the late afternoon. Overnight temperatures falling to between 17 and 21 with daytime temperatures reaching 30 to 36.
Illawarra Coastal Waters
Port Hacking to Ulladulla- Wind
- Northwest to southwesterly 10 to 15 knots tending northeast to southeasterly in the morning then tending north to northeasterly in the evening. Winds reaching up to 20 knots offshore north of Port Kembla during the afternoon and evening.
- Seas
- Around 1 metre, decreasing below 0.5 metres during the morning, then increasing to around 1 metre around midday.
- 1st Swell
- Northeasterly around 1 metre inshore, increasing to 1 to 1.5 metres offshore north of Port Kembla during the morning.
- Weather
- Partly cloudy. 50% chance of showers. The chance of a thunderstorm in the afternoon and early evening.
Boat Harbour Temperature Statistics View More
December Temperature
Point Perpendicular (2km)
Lowest 2 December, 2025
10.3 °CAverage December
20.4 °CHighest 5 December, 2025
33 °C
Climate (2020–Present)
Point Perpendicular (2km)
Average Low 2020–2025
14.7 °CAverage 2020–2025
17.4 °CAverage High 2020–2025
20.7 °C