Cairns weather in December

In December, Cairns has daytime highs averaging 29 °C, nights around 24 °C, with 15 wet days, and a sea temperature of 29 °C. Figures are 1991–2020 climate normals.

  1. Jan 27°
  2. Feb 27°
  3. Mar 26°
  4. Apr 24°
  5. May 23°
  6. Jun 21°
  7. Jul 20°
  8. Aug 21°
  9. Sep 22°
  10. Oct 24°
  11. Nov 25°
  12. Dec 26°

Daily temperatures through December

21°27°32°18152229
Daily highDaily low Day of month on the horizontal axis. Highs peak at 29.8 °C and lows bottom out at 23.8 °C.

How December develops

Averages for the first, middle and last part of the month, from daily 1991–2020 normals. Chance of rain is the share of years in which that calendar day recorded more than 1 mm.

DaysAvg highAvg lowChance of rain
1–10 December29.4 °C24.0 °C42 %
11–20 December29.5 °C24.2 °C45 %
21–31 December29.2 °C24.3 °C58 %
0%50%100%151015202530
Chance of a wet day (over 1 mm) by date in December. Wettest date over the 30 years: December 28, at 67 %. Single dates are noisy — read the shape, not the spikes.

What to expect

Measure Typical December Share of the month
Days above 25 °C 31 of 31 99 %
Days above 30 °C 9.8 of 31 32 %
Days below 0 °C 0 of 31 0 %
Days with more than 1 mm rain 15 of 31 49 %

Conditions in December

MeasureAverage
Mean temperature 26 °C
Record high (1991–2020) 36 °C
Record low (1991–2020) 20 °C
Relative humidity 82 %
Wind speed 14 km/h
Cloud cover 64 %

December compared with the months around it

Month Avg high Rainfall Cloud
January 29.4 °C 245 mm 74 %
February 29.3 °C 264 mm 74 %
October 27.3 °C 36 mm 45 %
November 28.5 °C 61 mm 52 %
December 29.3 °C 150 mm 64 %

See all twelve months for Cairns

Nearby destinations in December

Destination Avg high Wet days Sea
Cairns 29 °C 15 29
Townsville 31 °C 11 28

QuestionsDecember in Cairns, answered

How warm is Cairns in December?

Daily highs average 29 °C and nights fall to about 24 °C, a spread of 5.2 °C between afternoon and dawn. That makes December the 3rd warmest month of the year here.

Does it rain much in Cairns in December?

December averages 150 mm of rain, spread over about 15 of the 31 days — 49 % of the month. Cloud cover averages 64 % of the sky.

Is the sea warm enough to swim in December?

The sea averages 29 °C off Cairns in December. Most people find water below 20 °C bracing and above 25 °C comfortable for a long swim; this figure is a monthly surface average, so a sheltered bay on a still afternoon can be warmer.

How long are the days in December?

Cairns averages 13 hours between sunrise and sunset in December. Day length is computed from latitude and date, so it is exact rather than modelled — but it says nothing about how much of that time is sunny.

Data sources and method

Normal period
1991–2020
Dataset version
era5-1991-2020-scores1.1
Last processed

Measured values come from ERA5 reanalysis and are reproduced unchanged. Calculated by us: daylight hours, beach and comfort scores, monthly rankings, threshold day counts, chance of a wet day by date, ten-day averages within the month. Full formulas are on the methodology page.

Contains modified Copernicus Climate Change Service information 2026. Neither the European Commission nor ECMWF is responsible for any use that may be made of the Copernicus information or data it contains.