Alert archive / Georgia / Flash Flood Warnings in 2020
Flash Flood Warning 69, NWS Atlanta, GA
NWS Atlanta, GA issued this flash flood warning at Nov 11, 2020, 10:35 PM EST for DeKalb County, Fulton County, Gwinnett County, Georgia. It was in force for 6 hr. No storm report in the archive falls inside the area while it was in force.
The area
The outline as issued.
The facts
- Issued
- Nov 11, 2020, 10:35 PM EST (03:35 UTC)
- Expired
- Nov 12, 2020, 4:30 AM EST
- In force
- 6 hr
- Issued by
- NWS Atlanta, GA
- Area
- Storm-based polygon
- Flood severity
- None
Counties DeKalb County, GA, Fulton County, GA, Gwinnett County, GA
The radar
The Atlanta radar (KFFC), 62 km from the middle of the area, began a volume at 03:37 UTC, the scan nearest the moment this went out.
Open the radar archive at this moment
The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.
The nearest sounding before it
Peachtre/Fal Fld, GA (KFFC), launched 00:00Z, 3.6 hours before the alert went out and 59 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.
- Mixed-layer CAPE
- 410 J/kg
- Mixed-layer CIN
- -35 J/kg
- Mixed-layer LCL
- 759 m above ground
- 0-6 km bulk shear
- 18 kt
- 0-1 km storm-relative helicity
- 90 m²/s²
- 0-3 km storm-relative helicity
- 127 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
997
WGUS52 KFFC 120335
FFWFFC
GAC089-121-135-120930-
/O.NEW.KFFC.FF.W.0069.201112T0335Z-201112T0930Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Peachtree City GA
1035 PM EST Wed Nov 11 2020
The National Weather Service in Peachtree City has issued a
* Flash Flood Warning for...
Northwestern DeKalb County in north central Georgia...
Northeastern Fulton County in north central Georgia...
West Central Gwinnett County in north central Georgia...
* Until 430 AM EST.
* At 1035 PM EST, Doppler radar indicated heavy rain across the
warned area. Between 1.5 and 2 inches of rain have fallen. Flash
flooding is ongoing or expected to begin shortly.
HAZARD...Flash flooding caused by heavy rain.
SOURCE...Doppler radar.
IMPACT...Flooding of small creeks and streams, urban areas,
highways, streets and underpasses as well as other
drainage and low lying areas.
* Some locations that will experience flash flooding include...
Atlanta, Decatur, Sandy Springs, Roswell, Johns Creek, Alpharetta,
Dunwoody, East Point, Duluth, Lilburn, Chamblee, Norcross,
Doraville, Clarkston, Berkeley Lake, North Atlanta, North Druid
Hills, North Decatur, Tucker and Druid Hills.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Be especially cautious at night when it is harder to recognize the
dangers of flooding.
Excessive runoff from heavy rainfall will cause flooding of small
creeks and streams, urban areas, highways, streets and underpasses
as well as other drainage areas and low lying spots.
&&
LAT...LON 3368 8442 3374 8453 3383 8447 3383 8446
3384 8446 3397 8438 3404 8437 3411 8431
3409 8419 3401 8413 3390 8412 3381 8423
FLASH FLOOD...RADAR INDICATED
$$The office that day
Everything else NWS Atlanta, GA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Nov 12, 12:05 AM EST | River Flood Warning | FFC | Forsyth, Fulton | 6 hr |
| Nov 12, 12:20 AM EST | Special Weather Statement | FFC | Towns, Union, White | 40 min |
| Nov 12, 1:37 AM EST | Flash Flood Warning | FFC | Towns, White | 5 hr |
| Nov 12, 3:49 AM EST | Special Weather Statement | FFC | Houston, Twiggs | 41 min |
| Nov 12, 4:13 AM EST | Flash Flood Warning | FFC | Greene, Oglethorpe, Putnam | 6 hr |
| Nov 12, 4:16 AM EST | Flash Flood Warning | FFC | Houston | 6 hr |
| Nov 12, 4:27 AM EST | River Flood Warning | FFC | Forsyth | 7 hr |
| Nov 12, 5:24 AM EST | Flash Flood Warning | FFC | Baldwin, Hancock | 6 hr |
| Nov 12, 6:01 AM EST | Flash Flood Warning | FFC | Taliaferro, Warren, Wilkes | 6 hr |
| Nov 12, 6:03 AM EST | Flash Flood Watch | FFC | Baldwin, Glascock, Hancock, Jefferson, Taliaferro, Warren and 3 more | 5 hr |
| Nov 12, 6:40 AM EST | River Flood Warning | FFC | Forsyth, Fulton | 30 hr |
Nearby
Flash Flood Warnings in Georgia, 2020Every flash flood warning in 2020
Sources
The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.