Sydney weather in December
Sydney averages 26°C by day and 18°C at night in December, with the sea at 21°C and 10 days with at least 1 mm of rain. That is about 2°C warmer than November.
Day
26°C
Night
18°C
Sea
21°C
Rainy days
10
Flight from London
20½h
What December feels like
December is hot in Sydney: proper beach weather.
The sea is 21°C: fine for swimming without a wetsuit.
Expect some rain: about 10 days with at least 1 mm.
Of the 48 sun destinations we track, Sydney is the #20 warmest in December.
Want it warmer in December?
These are hotter than Sydney this month for at most an hour and a half more flying:
Sydney weather by month
December is highlighted. Compare with November and January, or see the full year in Sydney.
Sydney in December: quick answers
Is Sydney hot in December?
December is hot in Sydney: proper beach weather. Average highs are 26°C and lows 18°C.
Can you swim in Sydney in December?
The sea is 21°C: fine for swimming without a wetsuit.
Does it rain in Sydney in December?
Expect some rain: about 10 days with at least 1 mm.
What is the warmest month in Sydney?
January, at an average high of 27°C. The coolest is June at 17°C.
How long is the flight to Sydney from the UK?
About 20½h direct from London, estimated from the 17,016 km distance. Check your airline for exact times.
Still choosing? See where is hot in December for every destination ranked by temperature, sea and flight time.
How we measured this
Averages of every day in December from 2016 to 2025, from the Open-Meteo historical weather archive (ECMWF ERA5 reanalysis). Sea temperature is the 2023 to 2025 average from the Open-Meteo marine archive. A rainy day has at least 1 mm of rain. Reanalysis describes an area about 25 km across, so sheltered resorts can run a degree or two warmer. Flight time is a distance-based estimate from London Heathrow.
Planning Sydney in December?
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