Climate Insights for Arlington Heights

The climate in Arlington Heights is cool. The average annual temperature is 9°C and approximately 2567mm of precipitation falls per year. Arlington Heights receives a notable amount of rainfall throughout the year, including during its driest month. Arlington Heights is in the Northern Hemisphere. Summer begins at the end of June and lasts through September. The summer months are: August, July, September. The coldest months are February, December, January, when temperatures can drop to 0°C. Arlington Heights experiences heavy snowfall, typically from January through December.

Temperatures in Arlington Heights vary considerably across the year, with a 25°C difference between the coldest and warmest months. August is the warmest month, though highs remain moderate at 25°C with a mean of 18°C. The coldest month is February, when overnight lows fall to 0°C and the daily average is 3°C. On average, daily temperatures fluctuate by about 9°C between overnight lows and afternoon highs. The sharpest temperature change occurs between September and October, with a 5°C shift in average temperatures.

Arlington Heights is a very wet location, receiving approximately 2567mm of precipitation annually, which averages out to around 214mm per month. The wettest month is December, averaging 381mm of rainfall. November and January also tend to see above-average precipitation. The driest month is July, with just 33mm. That's 348mm less than December, the wettest month. Rainfall is heavily concentrated in certain months, creating a distinct wet and dry season. Visitors should plan around these patterns, as the difference between peak and low months is dramatic. Arlington Heights receives heavy snowfall, accumulating around 245cm annually from January through December. The snowiest month is February, with approximately 76cm. Winter travel should account for significant snow cover.

Arlington Heights is relatively calm, with an average annual wind speed of 6km/h. For context, sustained winds below 12km/h are generally light, while anything above 25km/h is considered strong. The windiest month is January, averaging 7km/h, though still comfortable for most outdoor activities. The calmest conditions occur in August, with average winds dropping to 5km/h, making it an ideal period for wind-sensitive activities. There is moderate seasonal variation in wind speed, with a 2km/h gap between the calmest and windiest months.

It is currently summer in Arlington Heights, which began on June 21, 2026. Arlington Heights is in the Northern Hemisphere, where spring begins in March, summer in June, autumn in September, and winter in December. The warmest period peaks in August at around 25°C, while the coldest stretch bottoms out in February near 0°C. Autumn is next, beginning on September 23, 2026 (6 days from now).

The best time to visit Arlington Heights is during July and August, when the weather is most comfortable for travellers. During these months, average temperatures hover around 18°C with modest rainfall averaging 42mm per month. By contrast, February can be quite cold with temperatures dropping to 0°C. A light rain jacket is recommended, though showers are generally brief and shouldn't disrupt your plans.

The table below shows monthly climate averages for Arlington Heights based on historical weather data. Min and max temperatures represent typical overnight lows and afternoon highs for each month, shown in degrees Celsius (°C). Precipitation is measured in millimetres (mm) and indicates the average total rainfall per month. Snow is measured in centimetres (cm) and reflects average monthly snowfall accumulation. Wind speed is the average sustained speed in kilometres per hour (km/h). All values are based on averages from over 10 years of historical weather data. The current month is highlighted for quick reference.