January weather forecastPerth, Australia

January
Weather in January
January in Perth, Australia brings in the New Year with a blend of warm temperatures and modest humidity. Characterized by a summery weather, the month commences with the city's highest annual temperature, reaching a scorching high of 31.3°C (88.3°F). As the first month of the year, January establishes the precedent for Australia's infamous heat, setting the beaches as ideal hangout spots for locals and tourists alike. The evenings cool down, providing a pleasant respite from the day's heat. Despite the high temperatures, rainfall in January is relatively light, allowing for plenty of outdoor activities.Temperature
The advent of January signifies a minor shift to an average high-temperature of a tropical 31.3°C (88.3°F), aligning closely with December. With a notable difference from peak temperatures, an average of 18.2°C (64.8°F) marks the nights in January.Humidity
In Perth, the average relative humidity in January is 39%.Rainfall
In January, the rain falls for 2.4 days. Throughout January, 15mm (0.59") of precipitation is accumulated. In Perth, during the entire year, the rain falls for 108.4 days and collects up to 725mm (28.54") of precipitation.Sea temperature
In Perth, the average seawater temperature in January is 21.9°C (71.4°F).Note: Swimming in 21.9°C (71.4°F) is not a pleasurable activity for the majority of people. Breathing becomes increasingly challenging as water temperature descends from 21°C (69.8°F) to 15°C (59°F).
Daylight
In Perth, Australia, the average length of the day in January is 13h and 58min.On the first day of the month, sunrise is at 5:13 am and sunset at 7:25 pm. On the last day of January, sunrise is at 5:40 am and sunset at 7:19 pm AWST.
Sunshine
The months with the most sunshine in Perth are January and December, with an average of 11.5h of sunshine.UV index
The months with the highest UV index are January and December, with an average maximum UV index of 12. A UV Index estimate of 11, and higher, represents an extreme health hazard from unsafe exposure to UV radiation for average individuals.Note: The UV index of 12 during January leads to these advisories:
Employ all critical precautions. Guarding against sun damage is essential. UV radiation from the Sun is most intense between 10 a.m. and 4 p.m. Try to avoid direct sunlight during this period. For a sun-safe wardrobe, go for clothes that are tightly woven and generously sized. Ensure the liberal application and reapplication of a broad-spectrum SPF 30+ sunscreen after each outdoor activity or swim, and every two hours. 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 January
Perth, Australia
- Average high temperature in January: 31.3°C
The warmest month (with the highest average high temperature) is February (31.7°C).
The month with the lowest average high temperature is July (18.4°C).
- Average low temperature in January: 18.2°C
The month with the highest average low temperature is February (18.4°C).
The coldest month (with the lowest average low temperature) is July (7.7°C).
Average humidity in January
Perth, Australia
- Average humidity in January: 39%
The month with the highest relative humidity is July (57%).
The month with the lowest relative humidity is February (38%).
Average rainfall in January
Perth, Australia
- Average rainfall in January: 15.4mm
The wettest month (with the highest rainfall) is July (144.7mm).
The driest month (with the least rainfall) is February (8.8mm).
Average rainfall days in January
Perth, Australia
- Average rainfall days in January: 2.4 days
The month with the highest number of rainy days is July (16.9 days).
The month with the least rainy days is February (2.1 days).
Average sea temperature in January
Perth, Australia
- Average sea temperature in January: 21.9°C
The best month for swimming (with the highest average sea temperature) is March (23.4°C).
The coldest months (with the lowest average sea temperature) are September and October (19°C).
Average daylight in January /
Average sunshine in January
Perth, Australia
- Average daylight in January: 14h and 0min
The month with the longest days is December (Average daylight: 14h and 12min).
The month with the shortest days is June (Average daylight: 10h and 6min).
- Average sunshine in January: 11h and 30min
The months with the most sunshine are January and December (Average sunshine: 11h and 30min).
The month with the least sunshine is June (Average sunshine: 5h and 54min).
Average UV index in January
Perth, Australia
- Average UV index in January: 12
The months with the highest UV index are January and December (UV index 12).
The months with the lowest UV index are June and July (UV index 3).





