Many visitors explore Chicago in the summer. There are many festivals, but there are also crowds; the weather is quite hot and humid; and hotels raise their room rates. Winter time brings very cold weather, but if you don’t mind this and you are interested in indoor activities, room rates are at their cheapest. Spring is the best time to visit Chicago. The weather is temperate from April through May but it can be a little unpredictable - some days are warm while others are cool. Fall is also considered one of the best times to visit the city. From September through the end of October the temperatures are warm and hotel rates are reasonable.
In January, Chicago’s coldest month, the city welcomes the new year with freezing temperatures of 32°F (0°C) for an average high and 18°F (-8°C) for an average low. Winter sports like hockey are very popular during this time of the year.
February sees small increases in the average high and average low temperatures, which range between 36°F (2°C) and 21°F (-6°C). This month also receives the smallest amount of rainfall in the year with precipitation levels of 2 inches (49 mm).
Chicago Weather in March: Spring sees a 10-degree jump in temperature with the average high climbing to 46°F (8°C). Average low temperatures remain quite cold at 30°F (-1°C).
April is relatively sunny in Chicago with 215 hours of sunshine. The average high temperature rises quickly to 59°F (15°C) for the second month of spring. The low temperature is 41°F (5°C).
In May, temperatures make another big jump. Both the average high and average low temperatures jump by 11 degrees each settling at 70°F (21°C) and 52°F (11°C) respectively.
June is the wettest month of the year with precipitation rates hitting 4 inches (103 mm). This coincides with another rise in temperature as the average high and average low temperatures range between 81°F (27°C) and 63°F (17°C).
Chicago Weather in July: The heat is on in July as it’s not only the hottest month of year but also the month that receives the most sunlight. Chicago receives 318 hours of sunlight in July while the average high temperature peaks at 84°F (29°C). The average low temperature is 68°F (20°C).
August is the second hottest month of the year with the average high and average low temperatures decreasing by 2 degrees each.
In September, average high and low temperatures make a considerable decrease. The average high temperature returns to a much cooler 75°F (24°C) while the average low temperature decreases nearly 10 degrees to 66°F (19°C).
October brings another big drop in temperature with the average high measuring in at 63°F (17°C). The average low temperature drops by a whopping 20 degrees to 46°F (8°C). Expected rainfall in October is 3 inches (82 mm).
Chicago Weather in November: Things start to get pretty chilly in November with the average high temperature dropping again by over 10 degrees to 48°F (9°C). The average low temperature sinks to 34°F (1°C).
December receives the least amount of sunlight in the year as it averages 106 hours of day light. As the second coldest month of the year, the average high temperature peaks at 36°F (2°C) while the average low temperature drops to 23°F (-5°C).
The best time to see the sights and sounds of Illinois, and Chicago in particular, is in April and May while the summertime crowds have not yet arrived. Many of Illinois’ festivals take place in the summer months. If big events like the Chicago Pride Festival or Chicago Blues Festival are your main reason for visiting Illinois, plan your trip between June through August. Outdoor activities like hiking and camping are fantastic in between September and October while winter activities can be enjoyed from November to March. Verified Resource: National Weather Service