CHICAGO — Rounds of powerful storms flooded basements, downed trees and caused widespread power outages throughout the area Monday.
As many as three inches of rain and 74 mile-per-hour winds were recorded at Midway Airport and another approximately 2 inches fell at O’Hare Airport as of 4:30 p.m. Monday, said Eric Lenning, a meteorologist with the National Weather Service. That was before another round of storms barreled through the area.
Chicago was under a flash flood warning through Monday evening as Chicagoans reported flooded basements and underpasses as well as power outages.
By 4 p.m. Monday, the Office of Emergency Management and Communication had already received 238 calls for water in basements, 286 calls for water on the street and 17 calls for flooded viaducts.
There were also more than 770 tree emergency calls, according to OEMC.
ComEd reported more than 2,600 power outages across Cook County. Outage updates will be posted here.
Dark skies loom over Edgewater ahead of a thunderstorm warning on July 27, 2026. Credit: Colin Boyle/Block Club Chicago
Beverly resident Chuck Gill said a tree from his yard fell on his car around 1:30 p.m. Monday.
“It was like a burst. It lasted like a minute and all of a sudden I looked out and [the branch] is on my car,” the 64-year-old said.
Gill noted the recent storms come as the Beverly area has faced a lot of weather-related damage in recent months. Two major storms plowed through the area in mid-June, causing widespread flooding and other issues on the Far South Side.
Chicago saw 5 inches of rainfall in June, according to National Weather Service data. A typical June in Chicago sees just over 4 inches.
Luckily, no one was hurt this time, Gill said.
“Cars can be replaced,” he said. “Lives can’t.”
Chuck Gill’s car was damaged when a tree branch fell on his car on July 27, 2026 during a severe thunderstorm. Credit: Jim Lynch/Block Club Chicago
In Belmont Cragin, strong winds led to downed limbs and power lines. Meineke Car Care Center at 4621 W. Belmont Ave. saw a fallen power line crash into cars parked at the business.
Charles McDonald manages the store and said the damage was extensive, including sparks burning a hole in the hood of a car and the pole piercing another car’s roof and windshield. Power went out at the business but it was promptly restored, McDonald said. ComEd responded to the downed lines but workers declined to comment on how widespread an outage was caused by the fallen lines.
The city is encouraging Chicagoans to report flooding, downed trees and damaged power lines at 311.chicago.gov or by dialing 3-1-1.
Streets and Sanitation Commissioner Cole Stallard previously told Block Club that a tree down in the middle of the street that prevents passage is one of the city’s top priorities after a storm. Other requests, like a tree crushing a parked car, is not deemed an emergency and is cleared at a later date, Stallard said.
A power line fell on cars parked at an auto business in Belmont Cragin on Monday, June 27, 2026. Credit: Michael Liptrot/ Block Club Chicago
How To Deal With Flooded Basements
Roy Spencer, founder and president of Perma-Seal, a Chicago-area business specializing in waterproofing basements, said neighbors with flooded basements should never walk into flood waters as there may be loose wire or exposed electric lines which can be extremely dangerous.
Instead, residents should ensure their power is off before walking into a flooded basement, Spencer said.
He said residents who cannot reach their power box should contact ComEd to assist in turning off their electricity.
Cars splash through standing water on a flooded Montrose Avenue in Uptown after a thunderstorm warning on July 27, 2026. Credit: Colin Boyle/Block Club Chicago
Spencer also said basement floodwater could be contaminated. Chicago’s Rainblocker program attempts to prevent the city’s sewer main from reaching capacity through restrictor valves placed in stormwater catch basins on streets with the goal of ensuring that dirty water does not enter people’s homes. However, the city’s website admits the program “is clearly still a work in progress.” The city says some homes that flooded with a foot of water or more in the past might only experience an inch or two now.
Once the power has been shut off, Spencer said residents should check the sump pump — the device that pumps excess groundwater away from the house’s foundation, usually found at the lowest level of the basement.
“The number one most likely cause of a flooded basement is your sump pump has failed,” Spencer said. “If your sump pump doesn’t work, all that water builds up and it’ll start coming up through or around the floor.”
If the sump pump isn’t the cause of the flooding, chances are the city’s storm sewer is coming up into the basement, Spencer said. Chicago’s naturally flat landscape makes the city especially prone to flooding, according to the Metropolitan Water Reclamation District of Greater Chicago.
Heavy rain whips at Foster Beach during a thunderstorm in Edgewater on July 27, 2026. Credit: Colin Boyle/Block Club Chicago
If the city sewer is backed up, “the water won’t go down the drain, it’ll literally come up the drain,” causing an overwhelm in the sump pump system, Spencer said.
Experts also recommend checking your sump pump annually, ideally in the spring, to ensure it is working properly ahead of summer storms. This includes making sure there is no material obstructing the pump and making sure the pump is plugged in.
Always make sure to document flooding by taking pictures and videos to help maintenance services like Perma-Seal determine the problem, Spencer said.
