Illinois weather in July
Thinking about venturing to Illinois this July and curious about the weather conditions to expect? This page holds all the key information you seek, responding to your question:
What is the weather like in Illinois in July?
Illinois is a region in the United States of America. July in Illinois generally has temperatures that range from warm to very warm, with precipitation levels ranging from moderate to high. July falls during the summer season.
Based on our climate data spanning from 1990-2020, the average maximum temperature is warm in Roscoe at 26°C to very warm in O'Fallon at 31°C. Nighttime temperatures generally drop to 20°C in O'Fallon and 14°C in Roscoe. In Illinois, July typically stands out as the hottest month of the year. If you're planning a visit during this time, it would be wise to come prepared. Packing light and breathable summer cloths will ensure you stay comfortable throughout your stay.
In July, precipitation varies across different areas. From moderate rainfall in Taylorville with an average of 85 mm to high rainfall in Galena with 154 mm. Meanwhile, Chicago enjoys approximately 319 hours of sunshine, offering a mostly sunny climate that adds a pleasant and vibrant feel to the month.
For specific regional insights in Illinois for July, refer to the map provided below. For an in-depth overview of the yearly weather conditions, do visit our Illinois climate page.
Where to go in Illinois in July
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Popular destinations in Illinois
What is the weather like in July for the 5 most popular destinations in Illinois?
Average weather in Chicago
In July Chicago generally has high temperatures with maximum daytime temperatures around 29°C, minimum nighttime temperatures around 19°C and high monthly rainfall. So on average the conditions are pleasant that month.
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Average weather in Schaumburg
In July Schaumburg generally has high temperatures with maximum daytime temperatures around 29°C, minimum nighttime temperatures around 17°C and high monthly rainfall. So on average the conditions are pleasant that month.
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Average weather in Rosemont
In July Rosemont generally has high temperatures with maximum daytime temperatures around 29°C, minimum nighttime temperatures around 19°C and high monthly rainfall. So on average the conditions are pleasant that month.
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Average weather in Joliet
In July Joliet generally has high temperatures with maximum daytime temperatures around 29°C, minimum nighttime temperatures around 18°C and high monthly rainfall. So on average the conditions are pleasant that month.
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Average weather in Naperville
In July Naperville generally has high temperatures with maximum daytime temperatures around 29°C, minimum nighttime temperatures around 17°C and high monthly rainfall. So on average the conditions are pleasant that month.
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Is your destination not in the list? Have a look at other destinations in Illinois, in the United States of America.
Is July the best time to visit Illinois?
In our opinion, July is a good time to visit Illinois with overall pleasant weather in Chicago.
Generally speaking, the best visiting conditions can be found in September offering mostly perfect weather in Chicago. On the other hand, the months of January, February, March, November and December tend to have poor weather conditions.
Interested in more climate information?
We have much more information about the climate in Illinois.
Interested in the weather conditions in a specific month? Select the month below.
Weather and climate has detailed information for every country in the world. Are you going to the United States of America? Get detailed historical weather averages for many cities in the United States of America.
Not sure yet where to go? We now have a tool which recommends destinations that suit your ideal climate conditions. Find out where to go with our weather planner.