The idea is to test the mutual aid box alarm system by running a simulated breakout of tornadoes.
More than 900 firefighters from Departments in Illinois, Wisconsin, Indiana and Michigan will take part.
"This exercise is a planned event and it's designed so no ones level of service from the standpoint of fire or emergency services is reduced," said Jay Reardon, MABAS chief executive officer.
The exercises will take place in Glenview, Hoffman Estates and Tinley Park. They are being done in conjunction with a meeting of fire chiefs going on at McCormick Place.
