Chicago, IL – Northern Illinois residents should prepare for patchy fog tonight, particularly near the Wisconsin-Illinois border. Forecasters predict steady rain will move in after midnight, impacting areas southeast of I-55. According to the National Weather Service, the highest rainfall totals are expected near and southeast of I-55, reaching up to 1.5 inches. Patchy fog is likely in northern Illinois, with the densest conditions expected closer to the Wisconsin border. Drivers are urged to exercise caution due to reduced visibility.