December weather forecastDee Why, Australia
December
Weather in December
Sea temperature
In Dee Why, Australia, the average seawater temperature in December is 21.9°C (71.4°F).Note: Most people do not find pleasure in swimming when the water temperature is 21.9°C (71.4°F). Breathing becomes increasingly difficult to manage as the water temperature drops from 21°C (69.8°F) to 15°C (59°F).
Daylight
With an average of 14h and 24min of daylight, December has the longest days of the year in Dee Why, Australia.On the first day of the month, sunrise is at 5:37 am and sunset at 7:50 pm. On the last day of December, sunrise is at 5:47 am and sunset at 8:08 pm AEDT.
Updated: Jan 26, 2024
Published by: Weather Atlas | About Us
Data Sources | Weather Forecasting & Climate
Published by: Weather Atlas | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
In December, the average sea temperature is 21.9°C (71.4°F). Swimming in 21.9°C (71.4°F) is not enjoyable for the majority. Controlling breathing becomes progressively more difficult as surface water temperature decreases below 21°C (69.8°F).
December has the longest days of the year in Dee Why, Australia, with an average of 14h and 24min of daylight.
In Dee Why, Australia, the average day length in December is 14h and 21min.
In December, on the first day of the month, sunrise is at 5:37 am and sunset at 7:50 pm. On the last day of the month, sunrise is at 5:47 am and sunset at 8:08 pm AEDT.
Average sea temperature in December
Dee Why, Australia
- Average sea temperature in December: 21.9°C
The best month for swimming (with the highest average sea temperature) is February (23.7°C).
The coldest month (with the lowest average sea temperature) is September (18.6°C).
Average daylight in December
Dee Why, Australia
- Average daylight in December: 14h and 24min
The month with the longest days is December (Average daylight: 14h and 24min).
The month with the shortest days is June (Average daylight: 9h and 54min).





