Arlington Heights (IL) Weather & Climate: Best Time to Visit
Average temperatures, rainfall, sunshine and the best time to visit Arlington Heights.
Climate overview of Arlington Heights
Arlington Heights, Illinois, United States of America, sees big temperature differences between seasons, with July peaking at 29°C (84°F) and January dropping to -1°C (30°F).
Rain/snowfall is high, totalling around 1040 mm (41 in) per year. June is the wettest month and January the driest. The city also experiences warm summers and very cold winters. July is the sunniest month, averaging 10.6 hours of sunshine per day.
Arlington Heights Weather by Month
Pick a month to see the average temperature, rainfall and sunshine in Arlington Heights - and find the best time to visit.
Monthly Temperature in Arlington Heights
Visitors to Arlington Heights can expect significant temperature changes throughout the year. Average maximum daytime temperatures range from a comfortable 29°C (84°F) in July, the warmest time of the year, to a very cold -1°C (30°F) during cooler months like January.
At night, you can expect temperatures ranging from 18°C (64°F) in July to around -9°C (16°F) during January.
Check out our detailed temperature page for more information.
Temperature ranges by month
Rainfall in Arlington Heights
Arlington Heights is known for its substantial rain/snowfall, with annual precipitation reaching 1040 mm (41 in). Significant seasonal changes in precipitation occur throughout the year. In the wettest month, June it receives high rainfall, averaging 124 mm (4.9 in) of precipitation, recorded across 14 rainy days. In contrast, the driest month January brings less snowfall, with 47 mm (1.9 in) over 10 snowy days. For more details, please visit our Arlington Heights 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 Arlington Heights
Seasonal changes in sunshine hours are quite dramatic in Arlington Heights. While July receives considerable daily sunshine with up to 10.6 hours, December marks the darkest time of the year, where sunshine is scarce with only 3.6 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 Arlington Heights by Month
The relative humidity is high throughout the year in Arlington Heights.
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 Arlington Heights
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 Arlington Heights
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
- Fewer rainy days: January, February, March, September and November
- 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 Arlington Heights
What is the best time to visit Arlington Heights?
September typically offers the most optimal weather in Arlington Heights. In contrast, January, February, March, November and December tend to have less optimal conditions. Arlington Heights has warm summers and very cold winters.
What temperatures can I expect in Arlington Heights?
Daytime highs range from -1°C (30°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 Arlington Heights get?
Annual rainfall is around 1040 mm (41 in). June is the wettest month with 124 mm (4.9 in), while January is the driest with 47 mm (1.9 in).
How sunny is Arlington Heights?
Arlington Heights 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, Arlington Heights enjoys abundant sunshine.
Arlington Heights 3-Day Forecast
Arlington Heights (IL) 3-Day Forecast
Arlington Heights on the map
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