Westmont (IL) Weather & Climate: Best Time to Visit
Average temperatures, rainfall, sunshine and the best time to visit Westmont.
Climate overview of Westmont
Temperatures in Westmont, Illinois, United States of America, vary greatly throughout the year. July is the hottest month at 29°C (84°F), while January is the coldest at 0°C (32°F).
The city receives considerable rain/snowfall, with around 1083 mm (43 in) annually. June is the wettest month. It has warm summers and very cold winters. July is the sunniest month, averaging 10.6 hours of sunshine per day.
Westmont Weather by Month
Pick a month to see the average temperature, rainfall and sunshine in Westmont - and find the best time to visit.
Monthly Temperature in Westmont
The climate in Westmont is known for significant temperature differences throughout the year, making the weather dynamic. Typically, average maximum daytime temperatures range from a comfortable 29°C (84°F) in July to a very cold 0°C (32°F) in the coolest month, January.
Nights vary from 18°C (64°F) in July to around -9°C (16°F) during the colder months.
Check out our detailed temperature page for more information.
Temperature ranges by month
Rainfall in Westmont
Westmont has a notably wet climate with abundant precipitation, recording 1083 mm (43 in) of rain/snowfall per year. The climate in Westmont shows significant variation throughout the year. Expect high rainfall in June, the wettest month, with an average of 129 mm (5.1 in) of precipitation over 15 rainy days.
In contrast, the driest month January offers drier and sunnier days, with around 52 mm (2 in) of snowfall over 13 snowy days. For more details, please visit our Westmont 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 Westmont
For those who appreciate different seasons, Westmont serves as an ideal destination. Expect longer, more sun-filled days in July with an average of 10.6 hours of sunshine daily, and embrace the darker days in December, offering only 3.6 hours of daily sunlight.
Visit our detailed sunshine hours page for more information.
Monthly hours of sunshine
Daily hours of sunshine
Daily percentage of sunshine
Humidity in Westmont by Month
The relative humidity is high throughout the year in Westmont.
The city experiences its highest humidity in December, reaching 76%. In May, the humidity drops to its lowest level at 64%. What does this mean? Read our detailed page on humidity levels for further details.
Relative humidity over the year
Wind Speed in Westmont
The mean wind speed over the year ranges from 4 m/s (8 knots) in June, July, August and September to 6 m/s (12 knots) in January, March and April. What does this mean?
The mean monthly wind speed over the year (meters per second)
Best Time to Visit Westmont
Monthly ratings reflect general weather comfort, based on daytime temperature and rainfall. Swimming and winter conditions are highlighted separately where relevant.
- Best overall: September
- Warmest weather: July and August
- Most sunshine: June and July
- Seasonal pattern: Warm summers and very cold winters
- Coldest conditions: January, with freezing nights around -9°C (16°F).
Frequently asked questions about the climate in Westmont
What is the best time to visit Westmont?
September typically offers the most optimal weather in Westmont. In contrast, January, February, March, November and December tend to have less optimal conditions. Westmont has warm summers and very cold winters.
What temperatures can I expect in Westmont?
Daytime highs range from 0°C (32°F) in January to 29°C (84°F) in July. Nighttime lows range from -9°C (16°F) to 18°C (64°F). Temperatures vary considerably through the year.
How much rain does Westmont get?
Annual rainfall is around 1083 mm (43 in). June is the wettest month with 129 mm (5.1 in), while January is the driest with 52 mm (2 in).
How sunny is Westmont?
Westmont receives around 2,509 hours of sunshine per year. July is the sunniest month with 319 hours, while December is the cloudiest with just 107 hours. Overall, Westmont enjoys abundant sunshine.
Westmont 3-Day Forecast
Westmont (IL) 3-Day Forecast
Westmont on the map
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