Alton is a city of approximately 27,000 people in Illinois, United States. Located in the Central Time Zone at 38.9°N latitude.
Alton has a humid continental climate. Average annual temperature is 57°F, with January lows around 24°F and July highs near 89°F. The city averages 41 inches of precipitation per year. The wettest month is typically May; the driest is February.