Tornado Warning!!!east central Grundy County in northeast Illinois... west central Will County in northeast Illinois...

823 PM CDT Tue may 28 2013 

The National Weather Service in Chicago has issued a 

* Tornado Warning for... 
east central Grundy County in northeast Illinois... 
west central Will County in northeast Illinois... 

* until 900 PM CDT 

* at 820 PM...a severe thunderstorm capable of producing a tornado 
was located near Mazon...and moving northeast at 35 mph. 

Hazard...developing tornado. 

Source...radar indicated rotation.