Alert archive / Georgia / Flash Flood Warnings in 2021

Flash Flood Warning 18, NWS Atlanta, GA

July 22, 2021Stewart County, Georgia

NWS Atlanta, GA issued this flash flood warning at Jul 22, 2021, 7:44 PM EDT for Stewart County, Georgia. It was in force for 3 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
Jul 22, 2021, 7:44 PM EDT (23:44 UTC)
Expired
Jul 22, 2021, 11:05 PM EDT
In force
3 hr
Issued by
NWS Atlanta, GA
Area
Storm-based polygon
Flood severity
None

County Stewart County, GA

The radar

The Maxwell AFB radar (KMXX), 94 km from the middle of the area, began a volume at 23:48 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 12:00Z, 11.7 hours before the alert went out and 138 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.

Skew-T log-pSkew-T log-p diagram, Peachtre/Fal Fld, GA at 12:00Z on 2021-07-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 420 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Peachtre/Fal Fld, GA at 12:00Z on 2021-07-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -7 square meters per square second.1939Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
420 J/kg
Mixed-layer CIN
-50 J/kg
Mixed-layer LCL
754 m above ground
0-6 km bulk shear
7 kt
0-1 km storm-relative helicity
-7 m²/s²
0-3 km storm-relative helicity
6 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

856 
WGUS52 KFFC 222344
FFWFFC
GAC259-230545-
/O.NEW.KFFC.FF.W.0018.210722T2344Z-210723T0545Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Peachtree City GA
744 PM EDT Thu Jul 22 2021

The National Weather Service in Peachtree City has issued a

* Flash Flood Warning for...
  Northern Stewart County in west central Georgia...

* Until 145 AM EDT Friday.

* At 744 PM EDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 1.5 and 2.5 inches of 
  rain have fallen. 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...
  Lumpkin, Charles and Louvale.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

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 3223 8488 3216 8472 3212 8471 3207 8473
      3205 8479 3205 8486 3216 8503 3218 8501
      3220 8496 3220 8497 3221 8498 3222 8497
      3222 8493 3222 8492 3223 8492

FLASH FLOOD...RADAR INDICATED

$$
1 follow-up statement
055 
WGUS72 KFFC 230305
FFSFFC

Flash Flood Statement
National Weather Service Peachtree City GA
1105 PM EDT Thu Jul 22 2021

GAC259-230315-
/O.CAN.KFFC.FF.W.0018.000000T0000Z-210723T0545Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Stewart GA-
1105 PM EDT Thu Jul 22 2021

...FLASH FLOOD WARNING IS CANCELLED FOR NORTHERN STEWART COUNTY...

The heavy rain has ended. Flooding is no longer expected to pose a 
threat.

LAT...LON 3223 8488 3216 8472 3212 8471 3207 8473
      3205 8479 3205 8486 3216 8503 3218 8501
      3220 8496 3220 8497 3221 8498 3222 8497
      3222 8493 3222 8492 3223 8492

$$

The office that day

Everything else NWS Atlanta, GA issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 21, 9:49 PM EDTSpecial Weather StatementFFCGwinnett41 min
Jul 21, 10:21 PM EDTFlash Flood WarningFFCGwinnett, Walton6 hr
Jul 22, 12:29 AM EDTRiver Flood WarningFFCGwinnett107 min
Jul 22, 4:24 PM EDTSpecial Weather StatementFFCCrisp36 min
Jul 22, 5:50 PM EDTSpecial Weather StatementFFCMacon25 min
Jul 22, 5:59 PM EDTSpecial Weather StatementFFCBleckley31 min
Jul 22, 6:05 PM EDTSpecial Weather StatementFFCMarion, Schley25 min
Jul 22, 7:06 PM EDTSpecial Weather StatementFFCStewart24 min
Jul 22, 7:57 PM EDTSpecial Weather StatementFFCWashington33 min

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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.