A powerful storm system is expected to bring multiple rounds of storms, capable of producing tornadoes and destructive wind and hail, to the Chicagoland area Wednesday, forecasters said.
The National Weather Service (NWS) said Tuesday that a powerful storm system will bring multiple rounds of thunderstorms on Wednesday, including the threat of a “dangerous outbreak” of damaging tornadoes and severe thunderstorms across the general region.
Two rounds of potentially severe storms are expected, with the first being in the morning into the early afternoon.
The storms may produce damaging winds and large hail, the NWS said.
A second, more dangerous round of potentially tornadic thunderstorms is expected late in the afternoon into early evening.
The NWS said there is high confidence in a large-scale pattern favorable for a regional severe weather outbreak, with the possibility of long-tracked, particularly damaging tornadoes.
There is uncertainty in how early storms could alter the setup on a smaller scale, leading to changes in the expected location and intensity of the potentially dangerous late-day storms.
It is also uncertain of the location of the highest risk for the most damaging tornadoes, the NWS said.
Graphics published by the weather service show the northern Illinois area marked at a three and four on a scale of five for severe weather threat level.
Flash flooding from waves of torrential rain is likely. The heavy rain could cause low visibility, with potentially two inches of rain in an hour, the NWS said.
Isolated to scattered storms may develop over far eastern Illinois and northwestern Indiana on Tuesday afternoon.
“While not widespread, a few storms may produce damaging winds and hail. The threat will end from west to east across the area,” the weather service said.