Excessive heat watch in effect Monday through Tuesday in Chicago area; air quality alert issued for Sunday

An air quality alert and excessive heat watch have been issued for the Chicago area in the coming days, according to the National Weather Service.

The air quality alert starts at midnight Saturday and extends through the end of the day Sunday, though weather service meteorologist Brett Borchardt said it’s likely it will be extended through the end of Tuesday when the excessive heat watch ends.

“Heat waves and poor air quality go hand in hand,” Borchardt told the Sun-Times Saturday afternoon, noting that high humidity and stagnant masses of hot air can worsen the air quality.

A mix of heat and high humidity is expected to push the heat index above 100 degrees both Monday and Tuesday, though Tuesday is expected to be worse — mostly due to weak winds and clear skies — with the heat index having the potential to break above 110 degrees. Even at night, more vulnerable populations, like children and the elderly, are at risk.

Borchardt said people should be stay indoors, hydrate and check up on loved ones. Those with breathing complications are also advised to stay inside as much as they can.

“This is the type of heat where people may want to reconsider their plans,” Borchardt said. “This looks like it’s going to be the hottest air of the season, certainly the hottest so far.”

The heat and humidity could also attract thunderstorms, though it was too early to tell if they would hit the area yet.

“Heat waves attract thunderstorms,” Borchardt said. “So we also encourage everyone to be prepared for thunderstorms if they occur unexpectedly.”