Historical weather data, all-time temperature records, and monthly climate averages for Glen Ellyn, IL. Explore typical weather conditions by week for trip planning, and see how today compares to the historical record.
April 4th in Glen Ellyn is a coin-flip kind of day — there's a 49% chance of precipitation and the average high is just 52°, but the date has a wild range. It's swung from a bitter 13° low in 1975 to a shirt-sleeve 76° high in 2010, so pack accordingly.
Glen Ellyn's weather history is not for the faint of heart. The thermometer has hit 104° in June 1988 and plunged to -27° in January 1985 — a 131-degree spread — and a single July day in 2011 dropped 6.86 inches of rain on the town.
Summer is the main event here, with mid-July averaging a high of 85° and also bringing the most rain — about 1.16 inches in a typical week. January is the deep freeze, with highs averaging just 29°. Spring and fall move fast, so if you're visiting for mild weather, May and September are your best bets.