Severe thunderstorms brought large hail, high winds and flooding to McHenry County, causing large trees and power lines to come down and resulting in power outages on Saturday.
The National Weather Service (NWS) initially issued a severe thunderstorm watch around 2 p.m. Saturday in effect until Saturday evening.
The watch included Lake, McHenry, Will, Kane, Cook, DeKalb, Boone, DuPage, Kendall, Ogle, Winnebago and Stephenson counties.
The NWS said a line of strong to severe thunderstorms dropped southeastward out of southern Wisconsin.
Around 3:20 p.m., the NWS said that severe thunderstorms were located along a line extending from Hebron to Harvard to Marengo moving southeast at 30 mph.
The weather service then upgraded Lake County, McHenry County and Boone County to a severe thunderstorm warning.
The NWS said the severe storms were capable of producing damaging winds up to 60 mph and nickel-sized hail. Damage to roofs, siding and trees was possible.
Forecasters also warned of torrential rainfall that could cause flash flooding of roads, low-lying areas, fields and basements, and cause rapid stream and creek rises.
Fire departments across McHenry County were kept busy responding to dozens of storm-related calls on late Saturday afternoon into the evening.
The calls mainly involved power lines and poles down, as well as trees down on houses, cars and roadways.
Residents in the Cary, Algonquin and Crystal Lake areas reported large hail.
One resident in Cary said his house’s siding was covered in holes and all of the cars had dents in them from the hail, which a photo showed appeared to be ping pong size.
“Had been driving from Woodstock to Algonquin in the heart of the storm. So scary. The hail on the car was so loud. So much debris all over. Huge trees down. Some roads had a lot of water. [I] was so relieved we made it home okay,” a woman told Lake and McHenry County Scanner.
A woman in Cary said her boyfriend’s pickup truck was totaled after a very large tree fell directly onto it.
A woman in Fox River Grove said Algonquin Road was blocked in multiple places due to downed trees and branches.
Multiple people who were at or near the Walmart in Crystal Lake said the power went out and the roadway outside the store was flooding.
“[I] was stuck inside the Walmart with the water blasting through the doors all that way into the store front and power was out,” one woman said.
The storms came amid hot and humid weather with peak heat indices of 100 to 110 degrees.
Additional severe thunderstorms developed overnight into Sunday in the northeast Illinois area with a flood advisory being issued.
The NWS said flooding caused by excessive rainfall was expected in Lake, McHenry, Kane, DuPage and Cook counties.
Doppler radar indicated scattered torrential rainfall producing thunderstorms across the area, the NWS said.
Additional rainfall amounts of 1-2 inches were expected over the areas that received the heaviest rain, the advisory said early Sunday morning. “Runoff from the rain that has fallen and from additional rainfall will result in flooding.”
The Village of Cary said that Mayor Mark Kownick declared a state of emergency for the village due to severe and damaging weather conditions that caused serious damage and community-wide power outages.
The Village of Cary said they will be conducting brush pickup beginning the week of August 25.
ComEd reported around 9:30 p.m. Saturday that over 66,000 customers were experiencing power loss.
As of Sunday morning, the number of customers without power increased to over 73,000.
“We appreciate your patience as crews work to restore power after severe storms,” ComEd said.
ComEd said that based on the history of similar-sized storms, they expect 80% of the outages to be restored by 9 p.m. Sunday, with the remaining to be restored by 2 p.m. Monday.
58,000 ComEd customers were experiencing power outages as of 9:30 a.m. Sunday.