Williamstown Weather & Climate: Best Time to Visit
Average temperatures, rainfall, sunshine and the best time to visit Williamstown.
Climate overview of Williamstown
The climate in Williamstown, South Australia, Australia, is marked by large temperature swings across the seasons, ranging from 29°C (84°F) in January to 15°C (59°F) in July.
Rainfall is modest, totalling around 472 mm (19 in) annually. The city experiences a distinct dry season from October to April, with warm summers and mild winters. September tends to be the wettest month. The most sunshine falls in January, with an average of 10.9 hours of daily sunshine.
Williamstown Weather by Month
Pick a month to see the average temperature, rainfall and sunshine in Williamstown - and find the best time to visit.
Monthly Temperature in Williamstown
In Williamstown, temperatures differ significantly between summer and winter months. Average maximum daytime temperatures range from a comfortable 29°C (84°F) in January, the warmest time of the year, to a moderate 15°C (59°F) during cooler months like July.
At night, you can expect temperatures ranging from 15°C (59°F) in January to around 6°C (43°F) during July.
Check out our detailed temperature page for more information.
Temperature ranges by month
Rainfall in Williamstown
Williamstown's climate is marked by below-average rainfall, accumulating 472 mm (19 in) of precipitation yearly. Significant seasonal changes in precipitation occur throughout the year. In the wettest month, September it receives moderate rainfall, averaging 59 mm (2.3 in) of precipitation, recorded across 9 rainy days. In contrast, the driest month March brings less rainfall, with 18 mm (0.7 in) over 6 rainy days. For more details, please visit our Williamstown Precipitation page.
The mean monthly precipitation over the year, including rain, hail, and snow
The average number of days each month with precipitation
Sunshine Hours in Williamstown
Seasonal changes in sunshine hours are quite dramatic in Williamstown. While January receives considerable daily sunshine with up to 10.9 hours, June marks the darkest time of the year, where sunshine is scarce with only 4.7 hours of sunlight per day.
Visit our detailed sunshine hours page for more information.
Monthly hours of sunshine
Daily hours of sunshine
Daily percentage of sunshine
Humidity in Williamstown by Month
The relative humidity is moderate throughout the year in Williamstown.
The city experiences its highest humidity in June, reaching 61%. In January, the humidity drops to its lowest level at 36%. What does this mean? Read our detailed page on humidity levels for further details.
Relative humidity over the year
Best Time to Visit Williamstown
Monthly ratings reflect general weather comfort, based on daytime temperature and rainfall. Swimming and winter conditions are highlighted separately where relevant.
- Best overall: January, February, March, April, October, November and December
- Warmest weather: January and February
- Most sunshine: January
- Seasonal pattern: A distinct dry season from October to April, with warm summers and mild winters
Frequently asked questions about the climate in Williamstown
What is the best time to visit Williamstown?
January, February, March, April, October, November and December typically offer the most optimal weather in Williamstown. In contrast, June, July and August tend to have less optimal conditions. Williamstown has a distinct dry season from October to April, with warm summers and mild winters.
What temperatures can I expect in Williamstown?
Daytime highs range from 15°C (59°F) in July to 29°C (84°F) in January. Nighttime lows range from 6°C (43°F) to 15°C (59°F). Temperatures vary considerably through the year.
How much rain does Williamstown get?
Annual rainfall is around 472 mm (19 in). September is the wettest month with 59 mm (2.3 in), while March is the driest with 18 mm (0.7 in).
How sunny is Williamstown?
Williamstown receives around 2,768 hours of sunshine per year. January is the sunniest month with 326 hours, while June is the cloudiest with just 140 hours. Overall, Williamstown enjoys abundant sunshine.
Williamstown 3-Day Forecast
Williamstown on the map
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