December weather forecastGreenwich, Australia
December
Weather in December
The first month of the summer, December, is still a warm month in Greenwich, Australia, with an average temperature fluctuating between 17.9°C (64.2°F) and 25.8°C (78.4°F).Temperature
The transition from November to December sees an average high-temperature of a still moderately hot 25.8°C (78.4°F), indicating a minor variance from the prior month. The average low-temperature during December nights is an enjoyable 17.9°C (64.2°F).Humidity
The average relative humidity in December is 71%.Rainfall
In Greenwich, in December, during 14.8 rainfall days, 43mm (1.69") of precipitation is typically accumulated. Throughout the year, there are 169 rainfall days, and 647mm (25.47") of precipitation is accumulated.Sea temperature
In Greenwich, in December, the average water temperature is 21.9°C (71.4°F).Note: Most people find swimming in 21.9°C (71.4°F) unenjoyable. As the water temperature falls from 21°C (69.8°F) to 15°C (59°F), controlling one's breathing becomes harder.
Daylight
December has the longest days of the year in Greenwich, with an average of 14h and 24min of daylight.On the first day of the month, sunrise is at 5:37 am and sunset at 7:51 pm. On the last day of December, sunrise is at 5:47 am and sunset at 8:09 pm AEDT.
Sunshine
In December, the average sunshine in Greenwich, Australia, is 9.7h.UV index
The months with the highest UV index are January, February, November and December, with an average maximum UV index of 6. A UV Index reading of 6 to 7 represents a high threat to health from exposure to the Sun's UV rays for the average person.Note: In December, the UV index of 6 transforms into the following advice:
Conform to measures and uphold sun safety traditions. Warding off skin and eye harm is necessary. Stay in the shade and avoid direct Sun exposure from 10 a.m. to 4 p.m., a period when UV radiation is particularly strong, noting that parasols or canopies may not offer total sun protection. Always opt for UVA and UVB-resistant sunglasses on radiant days. Stay alert! Reflective properties of sand and water amplify the Sun's UV radiation.
Published by: Weather Atlas | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Greenwich, Australia
- Average high temperature in December: 25.8°C
The warmest month (with the highest average high temperature) is January (27.3°C).
The month with the lowest average high temperature is July (16.6°C).
- Average low temperature in December: 17.9°C
The month with the highest average low temperature is January (19.8°C).
The coldest month (with the lowest average low temperature) is July (9.7°C).
Average pressure in December
Greenwich, Australia
- Average pressure in December: 1013.4mbar
The month with the highest atmospheric pressure is June (1020.9mbar).
The month with the lowest atmospheric pressure is January (1012.9mbar).
Average wind speed in December
Greenwich, Australia
- Average wind speed in December: 13.9km/h
The windiest months (with the highest average wind speed) are January and August (14km/h).
The calmest month (with the lowest average wind speed) is April (12.2km/h).
Average humidity in December
Greenwich, Australia
- Average humidity in December: 71%
The month with the highest relative humidity is February (75%).
The months with the lowest relative humidity are August and September (66%).
Average rainfall in December
Greenwich, Australia
- Average rainfall in December: 43mm
The wettest month (with the highest rainfall) is February (92mm).
The driest month (with the least rainfall) is September (35mm).
Average rainfall days in December
Greenwich, Australia
- Average rainfall days in December: 14.8 days
The month with the highest number of rainy days is March (18.8 days).
The month with the least rainy days is August (10.1 days).
Average sea temperature in December
Greenwich, 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 /
Average sunshine in December
Greenwich, 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).
- Average sunshine in December: 9h and 42min
The month with the most sunshine is November (Average sunshine: 9h and 48min).
The month with the least sunshine is June (Average sunshine: 5h and 54min).
Average sunshine days in December
Greenwich, Australia
- Average sunshine days in December: 12.6 days
The month with the most sunshine days is August (17.9 days).
The month with the least sunshine days is March (8.8 days).
Average UV index in December
Greenwich, Australia
- Average UV index in December: 6
The months with the highest UV index are January, February, November and December (UV index 6).
The months with the lowest UV index are May, June, July, August and September (UV index 4).
Average cloud cover in December
Greenwich, Australia
- Average cloud cover in December: 37
The month with the most cloud cover is February (Cloud cover 42).
The month with the least cloud cover is August (Cloud cover 24).
Average visibility in December
Greenwich, Australia
- Average visibility in December: 10km
The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (10km).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (10km).
