Alert archive / Georgia / Flash Flood Warnings in 2021

Flash Flood Warning 19, NWS Atlanta, GA

July 23, 2021DeKalb County, Fulton County, Georgia

NWS Atlanta, GA issued this flash flood warning at Jul 23, 2021, 6:22 PM EDT for DeKalb County, Fulton County, Georgia. It was in force for 4 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 23, 2021, 6:22 PM EDT (22:22 UTC)
Expired
Jul 23, 2021, 10:27 PM EDT
In force
4 hr
Issued by
NWS Atlanta, GA
Area
Storm-based polygon
Flood severity
None

Counties DeKalb County, GA, Fulton County, GA

The radar

The Atlanta radar (KFFC), 46 km from the middle of the area, began a volume at 22:21 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

TimeReportWhereRemark
Jul 23, 6:30 PM EDTFLASH FLOOD1 Ene Sweet Auburn, GAFLASH FLOODING ALONG KROG AND LAKE AVE VIA SOCIAL MEDIA. WATER AT LEAST A FOOT DEEP ACROSS ROADWAY, SOME VEHICLES BEGINNING TO FLOAT.

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 12:00Z, 10.4 hours before the alert went out and 43 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 2021-07-23Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 158 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 2021-07-23The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 20 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
158 J/kg
Mixed-layer CIN
-159 J/kg
Mixed-layer LCL
1211 m above ground
0-6 km bulk shear
8 kt
0-1 km storm-relative helicity
20 m²/s²
0-3 km storm-relative helicity
36 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

152 
WGUS52 KFFC 232222
FFWFFC
GAC089-121-240430-
/O.NEW.KFFC.FF.W.0019.210723T2222Z-210724T0430Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Peachtree City GA
622 PM EDT Fri Jul 23 2021

The National Weather Service in Peachtree City has issued a

* Flash Flood Warning for...
  West Central DeKalb County in north central Georgia...
  Central Fulton County in north central Georgia...

* Until 1230 AM EDT Saturday.

* At 622 PM EDT, emergency management reported water over roadways 
  and several vehicles flooded after thunderstorms produced heavy 
  rain across the warned area. Between 2 and 3 inches of rain have 
  fallen. Flash flooding is ongoing. Interstate 20 westbound at the 
  Hill Street ramp is also flooded out.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Emergency management reported.

  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...
  Atlanta, Decatur, Grant Park-Zoo Atlanta, Midtown, Druid Hills, 
  Candler-Mcafee, Sweet Auburn, Turner Field, Little Five Points, 
  Virginia Highland, Kirkwood, Piedmont Park, West End, Lakewood 
  Park, Atlantic Station, Gresham Park and Panthersville.

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 3369 8437 3371 8441 3374 8443 3379 8442
      3381 8440 3380 8436 3375 8431 3372 8430
      3369 8431

FLASH FLOOD...OBSERVED

$$
1 follow-up statement
600 
WGUS72 KFFC 240227
FFSFFC

Flash Flood Statement
National Weather Service Peachtree City GA
1027 PM EDT Fri Jul 23 2021

GAC089-121-240237-
/O.CAN.KFFC.FF.W.0019.000000T0000Z-210724T0430Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
DeKalb GA-Fulton GA-
1027 PM EDT Fri Jul 23 2021

...FLASH FLOOD WARNING IS CANCELLED FOR WEST CENTRAL DEKALB AND 
CENTRAL FULTON COUNTIES...

Flood waters have receded. Flooding is no longer expected to pose a 
threat. Please continue to heed any remaining road closures.

LAT...LON 3369 8437 3371 8441 3374 8443 3379 8442
      3381 8440 3380 8436 3375 8431 3372 8430
      3369 8431

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 23, 12:59 PM EDTSpecial Weather StatementFFCTwiggs31 min
Jul 23, 1:33 PM EDTSevere Thunderstorm WarningFFCHouston, Twiggs42 min
Jul 23, 1:58 PM EDTSpecial Weather StatementFFCHouston32 min
Jul 23, 2:29 PM EDTSpecial Weather StatementFFCDooly31 min
Jul 23, 2:33 PM EDTSpecial Weather StatementFFCBibb27 min
Jul 23, 2:56 PM EDTSpecial Weather StatementFFCWilcox34 min
Jul 23, 3:36 PM EDTSpecial Weather StatementFFCJones24 min
Jul 23, 4:04 PM EDTSevere Thunderstorm WarningFFCLamar, Pike, Upson41 min
Jul 23, 4:12 PM EDTSpecial Weather StatementFFCForsyth33 min
Jul 23, 5:11 PM EDTSpecial Weather StatementFFCDeKalb34 min
Jul 23, 5:26 PM EDTSevere Thunderstorm WarningFFCDeKalb, Fulton34 min
Jul 23, 5:51 PM EDTSpecial Weather StatementFFCDeKalb24 min
Jul 23, 6:07 PM EDTSpecial Weather StatementFFCDeKalb38 min
Jul 23, 6:10 PM EDTSpecial Weather StatementFFCForsyth35 min
Jul 23, 6:46 PM EDTFlash Flood WarningFFCDeKalb4 hr
Jul 23, 7:01 PM EDTRiver Flood WarningFFCDeKalb96 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.