Historical weather data, all-time temperature records, and monthly climate averages for River Forest, IL. Explore typical weather conditions by week for trip planning, and see how today compares to the historical record.
April 4th in River Forest lands squarely in unpredictable spring territory — the average high is just 52° with a low near freezing at 33°, but the date has seen everything from a balmy 76° in 2010 to a brutal 13° back in 1975. Nearly half the time (49%) you can expect some precipitation, with a lingering 5% chance it falls as snow.
River Forest earns its Midwest stripes with a staggering 131-degree spread between its all-time extremes — a scorching 104° in June 1988 and a bone-crushing -27° in January 1985. When it rains, it can really pour: a single day in July 2011 dropped 6.86 inches, and a January 1999 snowstorm buried the area under 18.6 inches.
Summer is the sweet spot, with mid-July averaging a high of 85° and also bringing the year's heaviest rainfall at over an inch per week. Winter bites hard — January highs hover around 29-30°, making mid-January the coldest stretch of the year. Spring and fall offer pleasant transitions through the 60s, but both seasons come with a side of volatility.