December weather forecast
Perth, Australia

Closing the year, December in Perth is filled with the arrival of summer, bringing back familiar higher temperatures. To herald the summer, Perth experiences a significant rise in temperature, soaring to 29.1°C (84.4°F), alongside reduced rainfall of 10mm (0.39"). As the sun reaches its zenith, endless sunny days redefine the lifestyle of Perth's inhabitants. The warming temperature coupled with summer festivities make it a popular month for beach visits and water sports. December's weather sets the stage for grandeur New Year's Eve celebrations, bidding adieu to the year on a warm note.

Temperature

December's beginning signals an average high-temperature of a still moderately hot 29.1°C (84.4°F), barely different from November's 26.6°C (79.9°F). Perth undergoes a major shift from daytime highs, averaging an enjoyable 16.4°C (61.5°F) during the night in December.

Heat index

The heat index value for December is appraised at 29°C (84.2°F). Exposure and extended activity could potentially cause a state of fatigue and lead to heat cramps.
Note that heat index values are valued for light wind and location in the shade. When under direct sunshine, the heat index may be elevated by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'feels like' or 'real feel', evaluates the perceived heat by adding the effect of moisture in the air. The effect of weather is individual, with a variety of people experiencing it differently due to distinctions in body mass, height, and level of activity. Remember, direct sunlight exposure can heighten the heat impact and might increase the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values are quite important for children. Children usually face more risks than adults as their ability to sweat is less. Additionally, their larger skin surface in relation to their petite bodies and higher heat output due to their activities increases their vulnerability.

Humidity

In December, the average relative humidity is 41%.

Rainfall

In Perth, in December, it is raining for 3.9 days, with typically 10mm (0.39") of accumulated precipitation. Throughout the year, in Perth, there are 108.4 rainfall days, and 725mm (28.54") of precipitation is accumulated.

Sea temperature

In December, the average sea temperature in Perth, Australia, is 20.9°C (69.6°F).
Note: Swimming in water at 20.9°C (69.6°F) is not a pleasing experience for the majority. As the temperature descends from 21°C (69.8°F) to 15°C (59°F), controlling breathing becomes increasingly hard.

Daylight

December has the longest days of the year, with an average of 14h and 12min of daylight.
On the first day of December, sunrise is at 5:03 am and sunset at 7:08 pm. On the last day of the month, sunrise is at 5:13 am and sunset at 7:25 pm AWST.

Sunshine

January and December, with an average of 11.5h of sunshine, are months with the most sunshine.

UV index

January and December, with an average maximum UV index of 12, are months with the highest UV index in Perth. A UV Index value of 11, and more, symbolizes an extreme health hazard from exposure to the Sun's UV radiation for average individuals.
Note: A typical high UV index of 12 in December suggests the following recommendations:
Take all necessary precautions, as unprotected skin can burn in minutes. Be aware that the sun's UV radiation is strongest between 10 a.m. and 4 p.m. and try to reduce direct sun exposure during this period as much as possible. Always opt for UVA and UVB-resistant sunglasses on radiant days. Sunscreen of at least SPF 30 should be applied generously and reapplied often on overcast days, especially post swim or outdoor exercise.