Monday weather: Flood watch issued until midnight as heavy rains douse Chicago area

The National Weather Service issued a flood watch until midnight Monday as heavy rains and storms passed through northeastern Illinois, bringing the possibility of flash flooding.

The Chicago Office of Emergency Management and Communications is advising Chicagoans to shelter, take precautions and avoid flooded underpasses and viaducts. City officials are also urging residents call 311 to report flooded areas and basements.

Chicagoans should conserve water usage to prevent sewage overflow during the heavy rains, city officials said. Some suggestions include reducing shower time, not running the dishwasher and not doing laundry.

Officials said they expect periods of heavy rain and thunderstorms into the evening. Torrential rainfall can flood roads, fields and basements and cause rapid stream rises, the weather service said.

They also warned that locally heavy rainfall may cause flash flooding, particularly across northeastern Illinois north of I-80. A flash flood watch went into effect at 10 a.m. and will last through midnight for McHenry, Lake, Kane, DuPage and some parts of Cook County.

The weather service reported dangerous swimming conditions in Lake Michigan in Illinois and Indiana through Tuesday. Breezy onshore winds could cause waves of 5 to 9 feet, life-threatening currents and hazardous boating conditions.

Because the beach hazard warning is in effect until Tuesday evening, the weather service recommended staying out of the water and avoiding piers, lakeshore trails and shoreline structures.

The Bears canceled fan access Monday due to inclement weather. The team will still practice indoors, but fans won’t be allowed to watch.

“The health and safety of our fans, players, coaches, and all staff is our utmost priority,” the team said in a statement.

rjohnson@chicagotribune.com