Storms Wednesday – Two storm rounds are expected to hit the Chicago area Wednesday, with meteorologists warning of torrential rainfall, a risk of flash flooding and possible tornadoes—especially south of the city.
Clouds gathered for the Wednesday rush, and forecasters were already tracking the next punch aimed at the Chicago area: two storm fronts, more than one window for dangerous weather, and conditions that could shift quickly.
The first, described as the less severe round, is expected to move through between 9 a.m. and 1 p.m. It’s forecast to bring mostly showers, chances of thunderstorms, and localized damaging winds.
Then comes the second round—expected from 2 to 7 p.m.—with what the National Weather Service called “the better chance for severe weather.” South Side neighborhoods and southern Cook County are appearing at higher risk for more severe storms.
Weather service meteorologist David King said people should keep an eye on conditions Wednesday afternoon because “the morning and afternoon rounds — these are going to be very efficient rainmakers.” He warned that rainfall could be intense enough that rain rates exceed two inches per hour.
That threat is tied to a warm front surging north from central Illinois. King said Tuesday there is uncertainty about how far north it will reach, but it is possible it could extend past Interstate 80.
For tornado concerns, meteorologist Kevin Doom said the outlook looks “markedly better” south of Chicago, particularly south of Interstate 80. Doom added that this doesn’t eliminate the tornado threat in the city, but said the risk is much lower in Chicago than farther south.
Danger isn’t limited to wind. The National Weather Service said a beach hazard remains in effect through Thursday morning, with waves potentially reaching 4 to 6 feet high. The agency warned that swimming conditions could be life-threatening.
In the city, the rainfall message has a second layer: runoff and flash flooding. King said the heavy storms of last week left the area primed for trouble. and Wednesday’s downpours could bring a high risk of flash flooding—especially in the city and in places more prone to flooding. including viaducts.
On top of the meteorological warnings, local infrastructure officials issued a separate caution for how people use water. The Metropolitan Water Reclamation District of Greater Chicago put an Overflow Action Day alert into effect Wednesday. urging the community to conserve water use to reduce water entering sewers.
Before the severe weather arrives. King said Tuesday that the best time to prepare is when conditions are still calm enough to act. He urged residents to double-check that they have batteries. multiple ways to receive warnings. and a plan for where to go or what to do if severe thunderstorm warnings. tornado warnings. or flash flood warnings are issued.
Thursday, Friday and Saturday were forecast to be sunny, with temperatures in the 70s. But Wednesday will be the focus: forecasters are warning that the storms could deliver enough rain quickly to overwhelm systems and enough instability to make tornadoes a possibility—especially outside the city center.
Chicago storms torrential rainfall flash flooding tornado risk National Weather Service Overflow Action Day Metropolitan Water Reclamation District beach hazard