Update: Severe Thunderstorm Watch Extended

The National Weather Service has extended the severe thunderstorm watch for northern Illinois until midnight.

The watch includes Cook, Lake and McHenry Counties.

2:17 p.m.

All of northern Illinois is under a severe thunderstorm watch.

The National Weather Service issued the watch just after 1 p.m. for a number of counties, including Cook, Lake and McHenry.

The watch is in effect until 7 p.m.

The National Weather Service's Storm Prediction Center has placed all of northern Illinois in the slight risk category for severe weather. Thunderstorms could include wind gusts in excess of 60 miles per hour, heavy rain, hail to the size of quarters and cloud-to-ground lightning.