Forecasters have issued a watch for Lake and McHenry counties as severe thunderstorms with “destructive winds” of 80 mph and torrential rainfall are possible Tuesday morning into the afternoon.
The National Weather Service (NWS) issued a severe thunderstorm watch and hazardous weather outlook in effect until 2 p.m. Tuesday.
The watch includes Winnebago-Boone-McHenry-Lake, Will, Cook, Ogle, Lee, DeKalb, Kane, DuPage, LaSalle, Kendall, Grundy, Kankakee, Livingston, Iroquois and Ford counties.
The NWS said there is a significant thunderstorm risk with an associated Level 1 of 5 tornado risk and Level 3 of 5 damaging wind risk, along with an elevated flooding risk.
Scattered thunderstorms early Tuesday morning will present a localized risk of severe weather, primarily damaging winds.
A complex of thunderstorms is expected to move across the area from mid-morning into early Tuesday afternoon.
The storm will move toward the east-southeast at 30 to 40 mph but could move east at 50 to 65 mph if a bowing complex develops.
“If this complex materializes, it will likely be severe with damaging wind gusts as high as 80 mph. In addition, any of these thunderstorms will be capable of producing torrential downpours which may lead to localized flooding,” the NWS said in the outlook.
“Embedded tornadoes also cannot be ruled out with these storms,” the NWS added.
The winds associated with the storms could cause structural damage and down trees.
The torrential rainfall could cause flash flooding of roads, low-lying areas, fields and basements, along with causing rapid stream and creek rises.
An elevated thunderstorm risk and elevated flooding risk are also in place for Wednesday and Thursday.
There is a limited thunderstorm risk and an elevated flooding risk on Friday.
“An active and potentially stormy weather pattern will persist through the end of the week, with additional rounds of thunderstorms possible and an attendant risk of severe weather and flash flooding,” the NWS said.