Storms broke some rainfall records

The Atlanta Journal-Constitution

Last week’s storms produced record rainfalls that could make this Georgia’s wettest September on the books. The most intense rainfall occurred along an arc west of Atlanta from Carrollton to Acworth, where nearly 30-year-old records for daily precipitation were broken in Dallas and Carrollton.

But storms randomly bombed many parts of metro Atlanta with heavy cloudbursts during the week, unleashing several floods across some parts of the region while other communities nearby remained relatively dry, National Weather Service records show.

Wettest September?

Existing regional record totals prior to recent rains.

Location	Amount	Year
Statewide	12.32 inches	2004
Northwest Georgia	9.56 inches	1957
North Central Georgia	12.57 inches	2004
Northeast Georgia	16.38 inches	2004
Atlanta area*	5.30 inches	1956

(* Atlanta area’s total so far this September: 7.89 inches)

Bursts big and small

Last week’s storms broke a few one-day records. Two-day totals were similarly heavy in many spots, though not in others.

Location	Sept. 21-22 rainfall	Record 1-day rainfal	Date
Atlanta/Hartsfield-Jackson	2.13	6.68	Oct. 4, 1995
Allatoona Dam	5.22	5.89	Aug. 12, 1991
Alpharetta	6.09	9.24	Sept. 17, 2004
Ball Ground	6.72	6.23	Sept. 17, 2004
Carrollton**	8.25	7.66	Sept. 21, 2009
Covington	2.16	7.13	Feb. 27, 1902
Cumming	6.25	6.05	Feb. 21, 1961
Dallas**	13.87	8.43	Sept. 22, 2009
Gainesville	4.01	6.04	Sept. 2, 2004

(** new one-day records)

A very wet week

Rainfall totals for the eight-day period of Sept. 14-22 varied widely across the Atlanta area.

Location	Inches
Atlanta automated station	11.23
Northeast Atlanta automated station	13.19
Ball Ground	12.91
Canton	17.14
Cartersville	7.38
Covington	2.76
Decatur	13.07
Doraville	13.88
East Point	14.35
Kennesaw	20.37
Lawrenceville	19.32
Marietta	18.91
McDonough	3.81
Newnan	3.4
Winder	8.5

Note: The NWS uses a variety of methods to measure precipitation —radar-based estimates, automated weather observation stations and standardized rain gauges operated by volunteers. These figures are from automated or human-operated stations.

Sources: National Weather Service; NOAA National Climatic Center

Compiled by Russell Grantham