The National Weather Service is investigating more than two dozens paths of potential storm damage as they work to determine exactly how many tornadoes touched down in the Chicago area and parts of Illinois Monday evening.
The agency said six survey teams were out across northern Illinois and northwest Indiana Tuesday, just hours after a rare severe weather event downed and uprooted trees, tore apart roofs, shut down major roadways for days and left hundreds of thousands without power in the midst of dangerous heat.
"So far we have 29 different paths of potential damage that we will be investigating today and in the coming days to identify potential tornado tracks," the NWS posted on X Tuesday morning, warning that "due to the large number of areas of interest," their efforts could take days to complete.
Maps showed the Chicago area riddled with potential paths of damage.
"Dozens of circulations" were reported as the storms sparked "multiple tornadoes at the same time" Monday evening, the NWS reported.
The storms barreled through the area from west to east, with "radar indicated" tornadoes reported in several suburbs as the severe weather prompted watches and warnings in every Chicago-area county.
Local
The National Weather Service called the line a series of "destructive thunderstorms" while the NBC 5 Storm Team called it an "incredibly active night."
"It's been years and years since we've seen something like this," NBC 5 Storm Team Meteorologist Kevin Jeanes said.
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A "radar confirmed" tornado was reported near Sugar Grove and was moving into the Aurora area as of 9 p.m., according to NWS. Shortly after, another was confirmed near Oswego, moving east into Plainfield and southern Naperville.
Numerous other tornadoes were reported as the storms continued well into the evening hours, many wrapped in rain, making them nearly impossible to see until they had already arrived.
The series of "destructive" storms left behind a trail of damage.
The Chicago Fire Department noted that it was responding to "several" reports of porch collapse issues and downed trees.
An entire block of trees were reported down near 70th and Campbell, the department said.
In Joliet, there were numerous reports of power lines down across the city and several roadways were partially or completely blocked by trees or fallen branches, according to police.
Reports of downed trees flooded in from numerous other suburbs.
Chicago's O'Hare International Airport was under a ground stop as all departures headed for the airport were grounded "due to tornado" until at least 10:30 p.m. Trains on multiple Metra lines were halted "due to high wind warnings."
Hundreds of thousands were without power as of 10 p.m. across the area.
The storms mark the second straight day of severe weather to hit the area, with rare touchdowns reported in Chicago itself Sunday evening.
