Historical weather data, all-time temperature records, and monthly climate averages for Macomb, IL. Explore typical weather conditions by week for trip planning, and see how today compares to the historical record.
April 4 in Macomb typically lands in that awkward shoulder season—expect a high around 58° and a low of 35°, with just a 31% chance of rain. But history shows this date can surprise: it's hit 86° (1929) and plunged to 9° (1975), a swing of 77 degrees on the same calendar date.
Macomb's weather has seen genuine extremes over its 131-year record. The thermometer once hit a brutal 113° in August 1934 and cratered to -30° in February 1905—a range of 143 degrees. A single June day in 1905 also dumped 10.25 inches of rain, which remains the all-time wettest.
Summer is the clear headline here, with late July averaging highs of 88° and the overall peak month of July reaching 87°. If you're avoiding cold, late January is the nadir at just 33° for a typical high. Rain peaks in early June, so pack accordingly if you're visiting in that window.