
Quite a chunk (anywhere from 10% to 40% historically) of our September rainfall can be attributed to tropical systems (ranging from full-fledged hurricanes like Irene to merely the remnants of a system that once was tropical).
Several tropical systems affected Virginia in 1999, which contributed to our wettest September on record. Here are the tracks of those that passed through or came close to Virginia with rainfall in 1999:

You'll recognize some of the other years, like 2003, in the Top 10 (resulting from the Isabel bump in rainfall, which was similar to this year's Irene totals):

And 2006 is another year Virginians remember well because of Ernesto's impressive rainfall over central Virginia:

The closed low pressure system currently still stuck spinning around Chicago, IL will finally receive a kick from the upper-level jet stream by mid-week, allowing it to migrate eastward. Its trailing surface cold front will also sweep through central Virginia Wednesday, ending an entire week of muggy, cloudy, wet weather.
Stay with CBS6, we'll keep you ahead of the storm.
--Meteorologist Carrie Rose