April 3-5 Tornado Threat Appears to be centered up North

The overall tornado threat will keep in the Plains, but the latest run of the Storm Prediction Center's SREF indicates the ingredients will come together to make up to a 20% chance of significant tornadoes in Illinois. North and Central Illinois, specifically.

Significant tornadoes are different from regular tornadoes. Significant tornadoes are strictly F2 or higher on the Fujita scale.
That said, with extreme caution, The Weather Centre is prepared to issue a dangerous situation bulletin going into the event.