Williamstown (NJ) Weather & Climate: Best Time to Visit
Average temperatures, rainfall, sunshine and the best time to visit Williamstown.
Climate overview of Williamstown
Williamstown, New Jersey, United States of America, experiences significant temperature variation throughout the year. Summers bring daytime highs of 31°C (88°F) in July, while winters cool to 6°C (43°F) in January.
The city has a wet climate, receiving around 1267 mm (50 in) of rain/snowfall per year. Despite the high annual total, it has very warm summers and cold winters. June is the wettest month. July is the sunniest month, averaging 9.2 hours of sunshine per day.
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
Depending on the time of the year, temperatures range from very warm to chilly in Williamstown. On average, daytime temperatures range from a very warm 31°C (88°F) in July to a chilly 6°C (43°F) in January.
Nighttime temperatures range from 20°C (68°F) in July to -4°C (25°F) in January.
Check out our detailed temperature page for more information.
Temperature ranges by month
Rainfall in Williamstown
Williamstown has a relatively rain/snowy climate with high precipitation levels, averaging 1267 mm (50 in) of rain/snowfall annually. The amount of precipitation varies moderately throughout the year. The wettest month, June, sees around 139 mm (5.5 in) of rainfall, perfect for those who enjoy a bit of rain now and then. The driest month, February, still receives a respectable 77 mm (3 in) of rainfall. 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
In Williamstown, summer days are longer and more sunny, with daily sunshine hours peaking at 9.2 hours in July. As the darker season arrives, the brightness of the sun becomes less. December sees a soft sun for only 4.7 hours per average 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 high throughout the year in Williamstown.
The city experiences its highest humidity in September, reaching 72%. In April, the humidity drops to its lowest level at 61%. 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: May
- Warmest weather: July and August
- Most sunshine: June and July
- Fewer rainy days: January, February, August, September and November
- Seasonal pattern: Very warm summers and cold winters
- Coldest conditions: January, with freezing nights around -4°C (25°F).
Frequently asked questions about the climate in Williamstown
What is the best time to visit Williamstown?
May typically offers the most optimal weather in Williamstown. In contrast, January, February and December tend to have less optimal conditions. Williamstown has very warm summers and cold winters.
What temperatures can I expect in Williamstown?
Daytime highs range from 6°C (43°F) in January to 31°C (88°F) in July. Nighttime lows range from -4°C (25°F) to 20°C (68°F). Temperatures vary considerably through the year.
How much rain does Williamstown get?
Annual rainfall is around 1267 mm (50 in). June is the wettest month with 139 mm (5.5 in), while February is the driest with 77 mm (3 in).
How sunny is Williamstown?
Williamstown receives around 2,500 hours of sunshine per year. July is the sunniest month with 275 hours, while December is the cloudiest with just 140 hours. Overall, Williamstown enjoys abundant sunshine.
Williamstown 3-Day Forecast
Williamstown (NJ) 3-Day Forecast
Williamstown on the map
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