The National Weather Service has issued an Extreme Heat Watch for Cook County, including the city of Chicago, warning that a dangerous spell of heat and humidity is set to build from Monday and could rank among the most severe the area has seen in years.
The watch is due to take effect on Monday afternoon and run through Wednesday evening. According to NBC Chicago, forecasters expect the heat index — a measure of how hot it actually feels once humidity is taken into account — to climb above 105°F (41°C) and potentially reach as high as 110°F (43°C). Conditions are forecast to intensify across the three days: highs of 91°F to 95°F on Monday, with the heat index near 100°F, before rising into the mid-to-upper 90s on Tuesday, when it could feel like 106°F. Air temperatures are expected to peak at close to 98°F (37°C) by Wednesday.
Forecasters say the spell could bring the hottest temperatures the region has experienced in two years, as well as the longest run of days above 95°F in 14 years. While the watch applies specifically to Cook County, the weather service said extreme heat is likely to be felt across the wider area.
The chief concern is the risk to health. The National Weather Service has warned that heat-related illnesses such as heat exhaustion and heat stroke could increase significantly during the watch, and has urged residents to stay in air-conditioned spaces, drink plenty of fluids and check on neighbours, the elderly and others who may be vulnerable.
City authorities maintain a network of cooling centres for residents without access to air conditioning, and anyone concerned about a relative or neighbour can request a welfare check by calling the city’s 311 line, according to Chicago’s standing extreme-heat guidance. Medical emergencies should be reported to 911.
An Extreme Heat Watch indicates that hazardous conditions are possible but not yet certain. Should the forecast firm up, the weather service may upgrade the alert to an Extreme Heat Warning, at which point officials typically advise people to cancel outdoor activities and take further precautions. Residents are being encouraged to prepare now, before the worst of the heat arrives.
