When it comes to severe weather chances in the Rockford area recently, meteorologists have missed the mark a bit, and I'm not complaining one bit. Illinoisans all know what a tornado is by now, but what about its equally scary cousin the derecho? Derechos can be just as destructive as tornadoes but have one very big difference: the damage comes from one direction in a straight path. Derecho Chances in Northern IllinoisMeteorologists are warning Northern Illinois and Southern Wisconsin residents that the storms expected to move into the area tonight (Monday night) are favorable for a derecho, so we need to be prepared. When the winds kick up you need to take shelter, just like during a tornado warning.