Clean up is continuing in the far northeast suburbs where strong storms coupled with damaging winds overnight produced a funnel cloud near Wadsworth, officials from the National Weather Service announced.
However, those damaging storms are paving the way for a Friday afternoon heat wave that is expected to bring temperatures into the high 90s with a heat index in the low 100s.
The National Weather Service has issued a heat advisory starting at noon Friday as near record-breaking temperatures are expected after less severe thunderstorms move out of the area, officials said.
The advisory is expected to continue until midnight, the National Weather Service said.
The hot, humid air in the forecast has meteorologists warning citizens to check up on relatives and neighbors throughout the day, while meteorologists are urging anyone working or spending time outside Friday to wear light, loosefitting clothing and to drink plenty of water as heat-related illnesses are possible.
The Illinois EPA is expecting poor air quality levels throughout the Chicago area today and tomorrow due to the hot, sunny and calm weather in the forecast.
The agency is predicting "orange" air pollution levels, meaning the air quality will be "unhealthy for sensitive groups," including children, the elderly and people with lung diseases.
The heat comes on the heels of heavy storms that produced golf-ball sized hail in Chicago, while roofs were destroyed in Winthrop Harbor and trees were blown down in North Chicago, Waukegan and Wadsworth.
The funnel cloud was reported to the National Weather Service by a trained spotter at around 8:30 p.m. in North Chicago, while a second funnel cloud was reported in Wadsworth at 8:23 p.m., officials said.
Officials said they are still trying to determine if the funnel cloud touched down somewhere in or near Lake County, which would upgrade it to a light tornado.
Lake County sheriff's department officials said the northern half of the county was battered by strong winds with houses damaged by fallen trees and major power outages.
The winds were strong enough to rip the roof off the Winthrop Harbor Yacht Club and bring down trees in Waukegan and North Chicago, officials said.
A water spout was spotted in Winthrop Harbor, officials said, and in North Point Marina high winds damaged boats, tore sails, toppled light poles and snapped tree trunks, the weather service said.
Chicago skyscrapers were pelted with golf ball-sized hail, bringing traffic in the city to a near standstill and packing winds so strong they spun a grounded military cargo plane in Wisconsin.
As of 7 a.m. Friday, ComEd officials estimated 26,000 people still remained without power due to the storm. Originally, they said, about 100,000 customers were impacted by the powerful storms.
In the North suburban region about 19,500 customers were without power at 7 a.m. An additional 3,700 remained without power south of the city, 2,800 in the Chicago region and only a small number in the western region, said spokeswoman Arlana Johnson.
She said the utility expects that number to decrease significantly throughout the day as the 440 crews tend to the downed lines. However, she didn't have a time when the entire area would be brought back online.
The storm raced down through Lake Michigan coastal communities, ducking further inland before reaching the Windy City and losing strength once it moved into Indiana, said David Beachler, a meteorologist with the National Weather Service in Chicago. He said a gauge in Waukegan Harbor registered a hurricane-strength wind gust of 94 mph.
David Mann, a manager at Batten International Airport in Racine, Wis., said a wind gauge there registered a gust of 82 mph and that the storm caused a C130 military plane on display to pivot 45-50 degrees.
The Journal Times reported that up to 11,500 customers of We Energies were without power in Racine County as of 10 p.m.
As the storm moved southward into Chicago, it dumped heavy rain and hail the size of golf balls and even baseballs, said Casey Sullivan, a weather service meteorologist.
The storm also killed a Kenosha, Wis., man when a tree collapsed onto his motorcycle. Two other residents were injured when they touched live electrical wires, and a woman was treated for a broken hip after she was struck by debris from a shed, authorities said.
The rest of the holiday weekend looks to be favorable for outdoor activities, however. A 30 percent chance of showers is possible on Saturday when temperatures are expected to reach the upper 80s.
Sunday and Monday will be mostly sunny with highs in the lower 80s on both days, according to the weather service.
Daily Herald news services contributed to this report.