|A persistent low pressure system which had been located over the lower Mississippi Valley for much of the past week brought a prolonged period of heavy rain across north and central Georgia. The period of rain began on Monday (September 14th), and through Friday much of the forecast area had recorded 1-3 inches of rain with localized amounts of 5-10 inches recorded over eastern portions of the area between Atlanta and Athens, as well as in the Macon area. A listing of 8 day rainfall totals across the area beginning September 14, 2009 at 8 AM EDT and ending September 22, 2009 at 8 AM EDT
The low pressure system began to weaken as it lifted north/northeast this weekend. This system provided a southwest flow of deep Gulf moisture across the Southeast. Surface high pressure building south along the eastern seaboard provided additional Atlantic moisture across the forecast area. The combination of these systems, aided by several upper level impulses, brought persistent heavy rainfall across portions of north and central Georgia where grounds were already saturated from rainfall throughout the past week beginning on Saturday. Heavy rainfall began across the Northeast Georgia Mountains Saturday morning, with additional heavy rain moving into the Atlanta metropolitan area by Saturday evening. Rainfall reports on Saturday showed 3-5 inches fell across portions of Northeast Georgia as well as across much of the Atlanta Metropolitan area. The heavy rainfall continued on Sunday...mainly impacting the Atlanta Metropolitan area during the afternoon and evening hours. 24 hour rainfall totals reported Monday morning showed rainfall amounts of more than 3 inches across portion of the metropolitan area with Douglas and Gwinnett counties hardest hit. Isolated areas in these counties received more than 9 inches with 11.80 inches of rainfall reported in Douglas county. Monday saw additional heavy rainfall across the area with 9 to 12 inches reported across western portions of the Atlanta Metropolitan area.
The heavy rainfall caused significant runoff into area streams and rivers, resulting in major to record flooding across the Atlanta metropolitan area. Numerous street and homes have been flooded, with portions of the downtown connector closed due to water over the road.
A list of record river crests for the September 19-21, 2009 event.
September 19-21, 2009
|Atlanta (ATL)||6.46 inches|
|Athens (AHN)||6.16 inches|
|Columbus (CSG)||1.46 inches|
|Macon (MCN)||5.58 inches|
|Peachtree City (FFC)||2.78 inches|
|Gainesville (GVL)||6.26 inches|
|West Fulton County (FTY)||8.22 inches|
|Chamblee (PDK)||8.96 inches|
|Cartersville (VPC)||5.28 inches|
|Rome (RMG)||4.22 inches|
from Cooperative Observers
September 19-21, 2009 (through 5:30 pm Monday)
|Dallas 7NE||15.44 inches (through 5:30 pm)|
|Alpharetta 4SSW||7.51 inches|
|Rainfall Maps ( click images to enlarge )|
24 hour Precip as of 8 am Sunday
48 hour Precip as of 9 pm Sunday
7 Days Precip as of 8 pm Sunday