From tweets sent at around 1 p.m. EDT by the National Weather Service northern Indiana weather forecast office (@nwxiwx):

Storms are expected to fire across the area around the 4-6 PM EDT timeframe. Line/bow echo expected to develop across Nrn. IL this eve…

Line/bow xpctd to race from IL/IN border to IN/OH border from 7 PM to 11 PM EDT timeframe. Wind gusts over 75 mph possible with the line.

Storms early will produce large hail 2″ or more possible, main threat becomes wind damage with the line/bow.

Tornadoes also possible along the warm front and at the northern end of the line/bow. Flash flooding possible as well along the warm front.

Please be prepared for large hail, extreme damaging winds and possible tornadoes late this afternoon into tonight! Stay tuned for updates.