After morning thunderstorms, Chicagoans can expect rain to continue Monday through midday, the National Weather Service said.
The NWS issued a tornado warning set to last until 10:15 a.m. for Naperville and other western suburbs, including Wheaton and Carol Stream, after a radar indicated a tornado had formed.
There is a chance that severe weather could further affect the Chicago area Monday, but the best chance of thunderstorms and strong winds is for parts of Illinois and Indiana south of Interstate 80, including Kankakee and Valparaiso, NWS meteorologist Casey Sullivan said.
The storm’s threats include brief torrential downpours, wind gusts over 50 mph and lighting strikes, the NWS said. The agency warned of possible tornadoes and winds strong enough to down tree limbs and fences in an advisory posted at 2:30 a.m., but later relaxed the warnings.
“The severe weather threat appears to be diminishing,” the NWS wrote on Twitter at 6 a.m.
A tornado formed near Champaign shortly before 9 a.m. Monday morning, videos showed. The NWS said a second tornado had been reported near Thomasboro shortly after the first tornado was observed.
Tornado warnings were in effect for Champaign, Urbana and Gifford at 9:45 a.m., with pea-sized hail possible, the NWS said.
While the worst of Chicago’s storms may have already passed, the rain will continue, Sullivan said.
“The showers are going to be ongoing at times, but the steady rain should be done by noon or 1 o’clock,” Sullivan said.
Patchy fog and breezes are expected Monday, with a predicted high of 51 degrees, according to the NWS.
The warmer-than-normal temperatures are expected to continue throughout the week, Sullivan said.
A mild high of 43 degrees is expected as Chicagoans head to the polls for Tuesday’s municipal election. The NWS forecasts partly sunny skies and light breezes — good weather for Election Day voters.
There is a chance for rain Tuesday night, and highs are expected to rise into the upper-40s Wednesday.
Temperatures are expected to drop Thursday into the mid-30s and remain there Friday.
“There is a chance of rain or snow Thursday night. The best chance is going to be Friday,” Sullivan said.