Heat index near 110: heat advisories in effect across northern Illinois

Dangerously hot and humid weather will persist in northern Illinois through Tuesday, with heat index values forecast to reach between 105 and 110 degrees in many locations, according to the National Weather Service.

Heat advisories are in effect for most of northern Illinois until 7 p.m. Tuesday. The combination of high temperatures and humidity will create conditions ripe for heat-related illness, particularly for those without access to air conditioning, older adults, and individuals with underlying health conditions.

According to the NWS Chicago office, the maximum heat index on Monday could reach 105 in DeKalb and 106 in Dixon and Kankakee. Joliet and Ottawa could see a peak heat index of 107.

Although a round of morning thunderstorms may limit heat in some areas Monday and again on Tuesday, forecasters cautioned that the risk remains elevated throughout the region. The threat level for heat impacts was rated a Level 2 (moderate risk), with warnings that prolonged exposure or physical activity during peak afternoon hours could be hazardous.

Residents are urged to take precautions: drink water frequently, stay in air-conditioned spaces when possible, wear light-colored clothing and take breaks if working outdoors. If you must be outside, consider shifting strenuous activity to early morning or evening hours.

For additional details, visit weather.gov/chicago or the NOAA HeatRisk site.