The July 27 storm system dropped 3 inches of rain at Midway and pushed 74 mph winds through the city. OEMC logged 238 basement flooding calls before 4 p.m. — before a second round arrived. For renters, the first question after the water recedes is whose job it was to prevent it.

By 4 p.m. Monday, Chicago's Office of Emergency Management and Communication had already logged 238 calls reporting water in basements — and the storms were not done.

The July 27 system dropped as many as 3 inches of rain and recorded wind gusts to 74 miles per hour at Midway Airport, National Weather Service meteorologist Eric Lenning told Block Club Chicago. O'Hare measured approximately 2 inches by 4:30 p.m., before a second round of storms moved through. A flash flood warning covered the city through the evening.

Alongside the basement calls, OEMC received 286 reports of water on streets and 17 calls for flooded viaducts. More than 770 tree emergency calls came in citywide. ComEd reported more than 2,600 power outages across Cook County.

For renters in older Chicago buildings, a flooded basement typically points to a maintenance failure rather than weather alone. Sump pump failure is the most common culprit, according to a contractor quoted by Block Club Chicago — when the pump cannot discharge the water load, groundwater backs up through floor drains rather than out of the building. In rental units, whether the landlord or tenant bears responsibility for pump upkeep depends on the lease and the city's habitability standards under the Residential Landlord and Tenant Ordinance.

Monday's event follows two major flooding rounds that struck Beverly and the Far South Side in mid-June. Chicago recorded 5 inches of rain in June against a historical average of just over 4, per National Weather Service data. July's tally is still accumulating.

Residents can report flooding, downed trees, and damaged power lines at 311.chicago.gov or by dialing 311.