Slow Moving Thunderstorms Prompt Flood Advisory

A Flood Advisory has been issued for Boone, McHenry and DeKalb counties until 10pm Wednesday evening.  Thunderstorms were quick to develop along a lake breeze late Wednesday afternoon north of Rockford, stretching down near Genoa.  The storms are very slowly lifting north and northeast but not before bringing nearly two inches of rain in less than two hours.

The storms are moving slowly due to weak wind

flow in the jet stream.  Winds overhead are not very strong throughout the atmosphere so as the storms develop, they tend to sit in one place for a while.  And because there is so much moisture in the atmosphere the storms are very efficient at producing significant amounts of rain.

The storm threat will continue through 10pm with isolated thunderstorms lasting through Midnight.  After that it'll be another muggy night and start to Thursday.