September Rainfall and Precipitation in Illinois
Average rainfall, rainy days and the driest cities in Illinois, the United States of America in September.
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Best Places to Visit in Illinois in September
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Monthly precipitation
0 mm (0 in) dry → 150 mm (5.9 in) wet
Marker color shows total monthly precipitation in September: pale blue is dry, deep blue is wet.
Illinois precipitation in September: frequently asked questions
How much rainfall does Illinois, the United States of America receive in September?
Chicago stays mostly dry in September, with average rainfall close to 95 mm (3.7 in).
How many days does it rain in Illinois, the United States of America in September?
On average, Chicago has about 9 days days of rain in September.
Is September part of the rainy season in Illinois, the United States of America?
Not really. September is outside the wettest stretch of the year in Illinois, the United States of America.
What is the wettest city in September in Illinois, the United States of America?
Based on our records, Roscoe receives the most rainfall in Illinois, the United States of America in September, averaging about 124 mm (4.9 in).
What is the driest city in September in Illinois, the United States of America?
The driest place is Freeport with an average rainfall of 70 mm (2.8 in) according to our data.
Interested in more climate information?
We have much more information about the climate in Illinois.
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