The National Weather Service has confirmed that it was a tornado – one of several in the Chicago area – that uprooted trees, snapped utility poles and tore the roofs off of businesses as it roared from roughly Burr Ridge to Stickney along the I-55 corridor on the evening of July 12.
The following day, based on a ground survey of the storm’s path, the National Weather Service reported it to be an EF-1 tornado with maximum winds approaching 110 mph.
The tornado missed the Landmark’s coverage area, barely.
Just south of the village, the tornado wreaked havoc, particularly in Countryside around Joliet Road and Willow Springs Road and Hodgkins around the intersection of LaGrange Road and Joliet Road, where the winds sheared the roofs from homes and businesses just after 6 p.m. There were no reports of anyone being injured.
Jeff Johnson, who was working at the Countryside Plaza shopping center on LaGrange Road a couple of blocks north of Joliet Road, witnessed the tornado firsthand.
“I looked out the window and saw a large rotating column of debris as it seemed to float through the intersection of Joliet and LaGrange roads, moving east,” Johnson said. “I’d never seen a tornado before, and although it didn’t look like something out of the ‘Wizard of Oz,’ I still knew it was a tornado and something pretty dangerous. I was worried for the people in the intersection and in its path.”
The tornado continued on its destructive path northeast into McCook, where it damaged roofs, snapped utility poles near Lawndale Avenue and Joliet Road and knocked down trees in the residential section of Lyons just north of 47th Street, east of Joliet Road.
The National Weather Service reported at least seven tornadoes in northeast Illinois between about 5 and 7 p.m. on July 12. In addition to the one that spun down the I-55 corridor in the southwest suburbs, tornados were reported as far north as Huntley in McHenry County and as far west as South Elgin in Kane County.
There was also a tornado reported on the ground around 7 p.m. near O’Hare Airport, with warehouses damaged on the west side of airport.
The tornados capped a volatile cycle of weather that began July 2-3, when between 6 and 9 inches of rain was dumped on Brookfield, Riverside and North Riverside. Another strong storm followed July 5, again overwhelming sewers still recovering from the earlier storm.
The Metropolitan Water Reclamation District of Greater Chicago reported on July 13 that its McCook Reservoir, the massive quarry that serves as the Deep Tunnel system’s storm outfall for the Landmark’s coverage area was at 92% of its capacity, holding 3.3 billion gallons of water.
Following the July 2 rain event, the McCook Reservoir was at 100% capacity, and there was so much storm water during that event that the MWRD took the rare step of reversing the flows of the Chicago River and North Shore Channel by opening the Lake Michigan locks downtown and in Wilmette, because the level of those waterways had exceeded the level of the lake.
According to an MWRD press release issued following the July 2 rains, the agency explained that it is only possible to open the locks when the river levels exceed the lake’s level. There is a misperception that there is some “magic switch” that can help alleviate flooding during localized heavy rains.
But opening the locks to reverse the Chicago River and the North Shore Channel can only be done when the river level is higher than the lake level.
The last time both the downtown and Wilmette locks were opened during the same storm was in May 2020, and they have been opened during the same storm just 10 times in the past 25 years.
“If we were to open the lock and gates too early, Lake Michigan would have a tsunami effect, overtaking the river and flooding everything in its path in downtown Chicago and along the waterways, totally decimating the riverwalk and municipalities downstream, on the South side and on the North side,” the press release stated. “The destruction that would be caused by opening the gates and lock too early is unimaginable.”