More than 200,000 homes and businesses across the Chicago area entered a second full day without electricity this week, and emergency officials are most worried about how people will get through it.
Portable generators kill roughly 100 people in the United States every year through carbon monoxide poisoning, according to the U.S. Consumer Product Safety Commission. Most of those deaths happen at home, during weather-related outages, in the days immediately after a storm. That is precisely the window the Chicago region is in right now.
The scale of the outage is why this matters more than usual. Two rounds of severe storms swept northern Illinois on Monday afternoon, and ComEd reported that more than 530,000 customers lost service at the peak. By Tuesday morning, roughly 215,000 to 230,000 remained without power, according to figures the utility provided to WTTW News and CBS News Chicago. The utility said it expected to restore 80 percent of interruptions by noon Wednesday and the vast majority of the rest by 10 p.m. Friday, July 31.
Why Generators Become the Deadliest Part of a Long Outage
Carbon monoxide is colorless and odorless, and a single portable generator produces as much of it as hundreds of cars. CPSC guidance is specific and unusually blunt: never run a generator inside a home, garage, basement, crawlspace, shed, or any enclosed space, and never on a porch or in a carport. Opening a door or a window does not make an enclosed space safe. The agency directs consumers to place generators outside only, at least 20 feet from the house, with the exhaust pointed away from the building.
"Hurricanes and severe storms can turn deadly long after the wind and rain stop," CPSC Acting Chairman Peter Feldman said in an agency warning issued earlier this year.
The risk is not theoretical for this region. Earlier this month, three children in Wayne County, Michigan died of carbon monoxide poisoning during storm-related outages after generators were run in a garage and a basement. Those deaths show that placement, not equipment failure, is the key danger.
Local agencies have echoed the same message. The Steger Fire Department, in the hard-hit south suburbs, told residents to keep any portable generator outside in a well-ventilated area and to treat every downed power line as live and dangerous.
The Hazards That Come with Cleanup, Not the Storm
Downed lines and unstable trees remain the second major risk, and the volume is substantial. Chicago's Office of Emergency Management and Communications received nearly 2,000 tree emergency reports through 311 by Tuesday morning, plus another 725 reports of tree debris. The agency also logged 569 reports of water on streets and 540 reports of water in basements.
Trees that fell onto power lines are slowing restoration. ComEd told customers that crews must assess damage, clear hazards, and rebuild infrastructure before power can be restored safely, and that in some places roads have to be cleared of downed trees before crews can reach damaged equipment. The utility described the region's weather this year as "becoming more frequent, more powerful and more destructive," noting its service area has already seen more storms in 2026 than in all of 2025.
Storm cleanup carries its own injury profile. Chainsaw wounds, falls from ladders, and contact with energized lines account for a large share of post-storm emergency visits. Flooded basements add a separate electrical hazard: standing water touching outlets, appliances, or a breaker panel can be lethal, and power should not be restored to a flooded home until an electrician has inspected it.
Search efforts continued this week for a contractor swept into a storm sewer in Downers Grove during Monday's rainfall. Officials have transitioned that operation from rescue to recovery.
One Correction Worth Noting: Heat Is Not the Current Threat
Coverage of this outage has widely paired it with heat risk, and on Monday that was accurate. The Chicago area was under a heat advisory with heat index values between 100 and 110 when the storms arrived, and the city's cooling centers were open. That context explains why heat was a concern then, even though it is not the same concern now.
That changed overnight. National Weather Service meteorologist Scott Baker told the Chicago Sun-Times that a cold front was expected to move through, bringing temperatures into the low 80s on Tuesday. Households without air conditioning are not currently facing the same danger they were on Monday.
With heat off the immediate list, families should prioritize carbon monoxide, downed lines, food safety, and refrigerated medication. Check generator placement, verify a carbon monoxide alarm on every level of the home, and review food and medication storage now so you know what to do next.
What Households Should Check While Power Is Out
Refrigerated medications are the item most often overlooked. Insulin, some biologics, and certain injectable drugs degrade at room temperature. Pack them in an insulated cooler with ice and call a pharmacist for guidance on the specific product rather than guessing. Do not discard or substitute a prescription without speaking to a clinician or pharmacist.
For food, a closed refrigerator holds a safe temperature for roughly four hours and a full, closed freezer for about 48 hours. When in doubt, throw it out.
Households with a member who depends on powered medical equipment, including oxygen concentrators, CPAP machines, or home dialysis, should contact their equipment supplier and their utility now rather than waiting. Residents can report outages to ComEd by texting OUT to 26633 or calling 1-800-334-7661. Spanish-speaking customers can call 1-800-955-8237.
Symptoms of carbon monoxide exposure include headache, dizziness, weakness, nausea, confusion, and blurred vision. Because the gas can cause unconsciousness before a person recognizes what is happening, anyone who suspects exposure should move to fresh air immediately, call 911, and not re-enter the building.
Never approach a downed line or a utility crew work zone. Call 911 for downed lines that pose an immediate hazard, and keep clear until crews secure the area.
What Happens Next
ComEd's stated target is restoration for the vast majority of remaining customers by the evening of Friday, July 31, with localized areas of severe damage potentially taking longer. The National Weather Service has been conducting damage surveys across DuPage and southern Cook counties to determine whether any tornadoes touched down, which will help clarify what happens next.
The American Red Cross opened shelters in Steger and Gurnee where residents can get food, charge devices, and access community resources. Residents can call 311 to request a well-being check on a neighbor or relative.
The confirmed situation is that a large share of the Chicago metropolitan area will remain without power into the end of the week. Households should place any generator outside only, keep a working carbon monoxide alarm on every level of the home, and seek help for refrigerated prescriptions or unsafe cleanup work. The open question is how many of the remaining outages involve damage severe enough to push restoration past Friday, so those households should plan accordingly.
Frequently Asked Questions
How many Chicago-area customers are still without power? More than 200,000 ComEd customers remained without service on the morning of July 28, down from a peak above 530,000 on Monday. ComEd expected 80 percent restored by noon Wednesday and most of the rest by 10 p.m. Friday, July 31.
Where should a portable generator be placed? Outside only, at least 20 feet from the house, with exhaust directed away from the building. CPSC guidance states that generators must never be run in a garage, basement, crawlspace, shed, carport, or covered porch, even with a door or window open.
What are the early signs of carbon monoxide poisoning? Headache, dizziness, weakness, nausea, confusion, and blurred vision. Because exposure can cause unconsciousness quickly, anyone who suspects it should move outdoors immediately and call 911 rather than waiting to see if symptoms improve.
Is the Chicago area still under a heat advisory? No. A heat advisory was in effect Monday with heat index values of 100 to 110, but the National Weather Service said a cold front moved through overnight and brought temperatures into the low 80s on Tuesday.
What should I do about refrigerated medication? Move it to an insulated cooler with ice and call a pharmacist about the specific product's temperature tolerance. Do not stop, substitute, or change a dose without speaking to a clinician.
How do I report an outage or a downed power line? Text OUT to 26633 or call ComEd at 1-800-334-7661. Spanish-speaking customers can call 1-800-955-8237. Call 911 for any downed line that presents an immediate danger, and never approach it.
