Yosemite National Park is definitely worth a visit
Vast forests, blue lakes, towering sequoias, and majestic waterfalls hint at the beauty of Yosemite National Park—a true natural masterpiece.
Harvey (IL) Weather & Climate: Best Time to Visit
Average temperatures, rainfall, sunshine and the best time to visit Harvey.
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Climate overview of Harvey
Temperatures in Harvey, 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).
Rain/snowfall is high, totalling around 1060 mm (42 in) per year. August is the wettest month and November the driest. The city also experiences warm summers and very cold winters. The sunniest month is July, with 10.6 hours of sunshine per day on average.
Harvey Weather by Month
Pick a month to see the average temperature, rainfall and sunshine in Harvey - and find the best time to visit.
Monthly Temperature in Harvey
The climate in Harvey is known for significant temperature differences throughout the year, making the weather dynamic. Average maximum daytime temperatures range from a comfortable 29°C (84°F) in July, the warmest time of the year, to a very cold 0°C (32°F) during cooler months like January.
At night, you can expect temperatures ranging from 19°C (66°F) in July to around -8°C (18°F) during January.
Check out our detailed temperature page for more information.
Temperature ranges by month
Rainfall in Harvey
Harvey has a notably wet climate with abundant precipitation, recording 1060 mm (42 in) of rain/snowfall per year. Significant seasonal changes in precipitation occur throughout the year. In the wettest month, August it receives high rainfall, averaging 122 mm (4.8 in) of precipitation, recorded across 11 rainy days. In contrast, the driest month November brings less rainfall, with 54 mm (2.1 in) over 8 rainy days. For more details, please visit our Harvey 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 Harvey
Seasonal changes in sunshine hours are quite dramatic in Harvey. 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
Data from: Chicago, the United States of America (46 KM, 28 Miles).
Daily hours of sunshine
Data from: Chicago, the United States of America (46 KM, 28 Miles).
Daily percentage of sunshine
Data from: Chicago, the United States of America (46 KM, 28 Miles).
Humidity in Harvey by Month
The relative humidity is high throughout the year in Harvey.
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
Data from: Chicago, the United States of America (46 KM, 28 Miles).
Best Time to Visit Harvey
For comfortable weather, consider visiting Harvey in September. Conditions are usually least favourable in January, February, March, November and December.
Monthly ratings reflect general weather comfort, based on daytime temperature and rainfall. Swimming and winter conditions are highlighted separately where relevant.
Jan
cold
Feb
cold
Mar
cold
Apr
mixed
May
very good
Jun
very good
Jul
very good
Aug
very good
Sep
excellent
Oct
good
Nov
cold
Dec
cold
- 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 -8°C (18°F).
Frequently asked questions about the climate in Harvey
What is the best time to visit Harvey?
September typically offers the most optimal weather in Harvey. In contrast, January, February, March, November and December tend to have less optimal conditions. Harvey has warm summers and very cold winters.
What temperatures can I expect in Harvey?
Daytime highs range from 0°C (32°F) in January to 29°C (84°F) in July. Nighttime lows range from -8°C (18°F) to 19°C (66°F). Temperatures vary considerably through the year.
How much rain does Harvey get?
Annual rainfall is around 1060 mm (42 in). August is the wettest month with 122 mm (4.8 in), while November is the driest with 54 mm (2.1 in).
How sunny is Harvey?
Harvey 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, Harvey enjoys abundant sunshine.
Harvey 3-Day Forecast
Harvey on the map
Harvey is highlighted - select any city to see its climate.
Popular in October
Where to go in October - average daytime high across popular destinations.
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