Rosemont (IL) Weather & Climate: Best Time to Visit
Average temperatures, rainfall, sunshine and the best time to visit Rosemont.
Climate overview of Rosemont
Rosemont, Illinois, United States of America, experiences significant temperature variation throughout the year. Summers bring daytime highs of 29°C (84°F) in July, while winters cool to 0°C (32°F) in January.
With around 1064 mm (42 in) of annual rain/snowfall, Rosemont has a notably wet climate. However, this rain/snowfall is not evenly distributed — the city has warm summers and very cold winters. The wettest month is June. The sunniest month is July, with 10.6 hours of sunshine per day on average.
Rosemont Weather by Month
Pick a month to see the average temperature, rainfall and sunshine in Rosemont - and find the best time to visit.
Monthly Temperature in Rosemont
Depending on the time of the year, temperatures range from comfortable to very cold in Rosemont. Average daytime temperatures reach a comfortable 29°C (84°F) in July. In January, the coolest month of the year, temperatures drop to a very cold 0°C (32°F).
At night, temperatures range from around 19°C (66°F) in July to -9°C (16°F) in January.
Check out our detailed temperature page for more information.
Temperature ranges by month
Rainfall in Rosemont
Rosemont has a relatively rain/snowy climate with high precipitation levels, averaging 1064 mm (42 in) of rain/snowfall annually. Rosemont can be quite wet during June, receiving approximately 126 mm (5 in) of precipitation over 14 rainy days.
In contrast, during the driest month (January), you will experience much drier conditions, with 50 mm (2 in) of precipitation spread across 10 snowy days. For more details, please visit our Rosemont 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 Rosemont
Rosemont can be enjoyed more throughout the sunniest month of July under a blue sky, with approximately 10.6 hours of sunshine daily. In contrast, the city experiences much darker days in December, 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 Rosemont by Month
The relative humidity is high throughout the year in Rosemont.
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 Rosemont
The mean wind speed varies between 4 m/s (8 knots) and 6 m/s (12 knots) throughout the year. It is lowest in June, July, August and September and highest during January, March and April. What does this mean?
The mean monthly wind speed over the year (meters per second)
Best Time to Visit Rosemont
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
- Fewest rainy days: February, 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 Rosemont
What is the best time to visit Rosemont?
September typically offers the most optimal weather in Rosemont. In contrast, January, February, March, November and December tend to have less optimal conditions. Rosemont has warm summers and very cold winters.
What temperatures can I expect in Rosemont?
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 19°C (66°F). Temperatures vary considerably through the year.
How much rain does Rosemont get?
Annual rainfall is around 1064 mm (42 in). June is the wettest month with 126 mm (5 in), while January is the driest with 50 mm (2 in).
How sunny is Rosemont?
Rosemont 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, Rosemont enjoys abundant sunshine.
Rosemont 3-Day Forecast
Rosemont (IL) 3-Day Forecast
Rosemont on the map
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