Alert archive / Georgia / Flash Flood Warnings in 2021
Flash Flood Warning 21, NWS Atlanta, GA
NWS Atlanta, GA issued this flash flood warning at Jul 24, 2021, 10:07 PM EDT for Barrow County, Gwinnett County, Hall County, Georgia. It was in force for 6 hr. 1 report came from inside the area while it was in force.
The area
The outline as issued, with what was reported inside it.
The facts
- Issued
- Jul 24, 2021, 10:07 PM EDT (02:07 UTC)
- Expired
- Jul 25, 2021, 4:15 AM EDT
- In force
- 6 hr
- Issued by
- NWS Atlanta, GA
- Area
- Storm-based polygon
- Flood severity
- None
Counties Barrow County, GA, Gwinnett County, GA, Hall County, GA
The radar
The Atlanta radar (KFFC), 95 km from the middle of the area, began a volume at 02:11 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.
What was reported inside it
| Time | Report | Where | Remark |
|---|---|---|---|
| Jul 24, 11:00 PM EDT | FLASH FLOOD | 1 Nw Hog Mountain, GA | WATER WAS REPORTED OVER THE ROADWAY NEAR THE INTERSECTION OF I-85 AND GRAVEL SPRINGS ROAD. |
Local storm reports filed while the alert was in force, from inside its polygon or its counties.
The nearest sounding before it
Peachtre/Fal Fld, GA (KFFC), launched 00:00Z, 2.1 hours before the alert went out and 91 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
- 703 J/kg
- Mixed-layer CIN
- -5 J/kg
- Mixed-layer LCL
- 1387 m above ground
- 0-6 km bulk shear
- 13 kt
- 0-1 km storm-relative helicity
- -5 m²/s²
- 0-3 km storm-relative helicity
- 47 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
998
WGUS52 KFFC 250207
FFWFFC
GAC013-135-139-250815-
/O.NEW.KFFC.FF.W.0021.210725T0207Z-210725T0815Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Peachtree City GA
1007 PM EDT Sat Jul 24 2021
The National Weather Service in Peachtree City has issued a
* Flash Flood Warning for...
Southwestern Barrow County in north central Georgia...
Eastern Gwinnett County in north central Georgia...
South Central Hall County in north central Georgia...
* Until 415 AM EDT Sunday.
* At 1007 PM EDT, Doppler radar indicated thunderstorms producing
heavy rain across the warned area. Between 1 and 2 inches of rain
have fallen. The expected rainfall rate is 1.5 inches in 1 hour.
Additional rainfall amounts of 1 to 2 inches are possible in the
warned area. Flash flooding is ongoing or expected to begin
shortly.
HAZARD...Flash flooding caused by thunderstorms.
SOURCE...Radar.
IMPACT...Flash flooding of small creeks and streams, urban
areas, highways, streets and underpasses as well as
other poor drainage and low-lying areas.
* Some locations that will experience flash flooding include...
Lawrenceville, Sugar Hill, Snellville, Suwanee, Buford, Braselton,
Auburn, Flowery Branch, Dacula, Grayson, Carl, Rest Haven, Hog
Mountain, Harbin and Rosebud.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Be especially cautious at night when it is harder to recognize the
dangers of flooding.
Be aware of your surroundings and do not drive on flooded roads.
Please report observed flooding to local emergency services or law
enforcement and request they pass this information to the National
Weather Service when you can do so safely.
&&
LAT...LON 3415 8397 3418 8387 3415 8384 3404 8383
3393 8380 3378 8399 3395 8407 3404 8407
3410 8404
FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL...1.5 INCHES IN 1 HOUR
$$The office that day
Everything else NWS Atlanta, GA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 24, 9:29 PM EDT | Special Weather Statement | FFC | Barrow, Gwinnett | 31 min |
| Jul 25, 3:43 AM EDT | River Flood Warning | FFC | Gwinnett, Walton | 4 hr |
| Jul 25, 9:25 AM EDT | River Flood Warning | FFC | Gwinnett | 11 hr |
Nearby
Flash Flood Warnings in Georgia, 2021Every flash flood warning in 2021
Sources
The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.