Rounds of spring storms brought rain, high winds, 70-degree temperatures, hail, flash flooding Thursday to the Chicago area — as well as hundreds of flight cancellations.
A tornado watch had been in effect until 8 p.m. for the western suburbs including in McHenry, Kane, Kendall and Grundy counties, according to Gino Izzi, a meteorologist with the National Weather Service, though no tornadoes had materialized by late Thursday.
The weather service gave the all clear for severe weather at 9:23 p.m., though thunderstorms continued later into the night.
“A watch means conditions favorable for storms to produce tornadoes,” Izzi said. “A warning means: ‘It’s coming.'”
The day also had seen some wild temperature swings, from 40 degrees at 8 a.m. at O’Hare, to Midway’s 70 degrees as of 3 p.m.
Flooding caused problems near O’Hare, where a ground delay was still in effect Thursday after 10 p.m. — following a ground stop 6:30 to 9:30 p.m. — leading to an average delay of 55 minutes and 719 canceled flights, according to the Chicago Department of Aviation. Midway was in a ground stop until 11:30 p.m., and saw 10 cancellations with an average delay of just over an hour.
On Friday, another temperature drop is expected in the city and the threat for severe storms will linger, though it’s uncertain whether those storms will reach the Chicago area due to the uncertainties of the front’s location and time of arrival, according to the weather service.
“During the afternoon tomorrow, it’ll be 42 downtown and in the 70s in the far south suburbs,” Izzi said.
The most intense storms could produce winds up to 70 mph, quarter-sized hail and the possibility of a tornado, the weather service said. Northwest Illinois was most at risk for a tornado, though one touching down had been possible anywhere in the Chicago area, officials said.
“It’s a lot of little things going on here today,” said Zachary Yack, a meteorologist at the weather service. “We just advise people to keep an eye on the forecast here today, and of course if one is issued for your area, seek proper precautions.”
The storm system behind the potentially severe weather was a “typical springtime storm system” moving through Kansas City into Iowa, Yack said. The Chicago area was on the “warm” side of the system, which is driving the showers and storms.