Alert archive / Georgia / Flash Flood Warnings in 2021

Flash Flood Warning 15, NWS Atlanta, GA

July 20, 2021Carroll County, Haralson County, Georgia

NWS Atlanta, GA issued this flash flood warning at Jul 20, 2021, 7:17 PM EDT for Carroll County, Haralson 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 20, 2021, 7:17 PM EDT (23:17 UTC)
Expired
Jul 21, 2021, 1:15 AM EDT
In force
6 hr
Issued by
NWS Atlanta, GA
Area
Storm-based polygon
Flood severity
None

Counties Carroll County, GA, Haralson County, GA

The radar

The Atlanta radar (KFFC), 66 km from the middle of the area, began a volume at 23:16 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 20, 7:30 PM EDTFLASH FLOOD3 Nnw Mount Zion, GANUMEROUS REPORTS OF ROAD CLOSURES DUE TO FLASH FLOODING IN CARROLL COUNTY.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Birmingham, AL (KBMX), launched 12:00Z, 11.3 hours before the alert went out and 160 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, Birmingham, AL at 12:00Z on 2021-07-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 690 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, Birmingham, AL at 12:00Z on 2021-07-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 28 square meters per square second.193958Sfc1 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
690 J/kg
Mixed-layer CIN
-3 J/kg
Mixed-layer LCL
524 m above ground
0-6 km bulk shear
18 kt
0-1 km storm-relative helicity
28 m²/s²
0-3 km storm-relative helicity
57 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

214 
WGUS52 KFFC 202317
FFWFFC
GAC045-143-210515-
/O.NEW.KFFC.FF.W.0015.210720T2317Z-210721T0515Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Peachtree City GA
717 PM EDT Tue Jul 20 2021

The National Weather Service in Peachtree City has issued a

* Flash Flood Warning for...
  West Central Carroll County in northwestern Georgia...
  Southern Haralson County in northwestern Georgia...

* Until 115 AM EDT.

* At 717 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 a half to 1 inch 
  is 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...
  Bremen, Mount Zion, Waco and Bowdon Junction.

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 3370 8534 3377 8510 3374 8506 3371 8505
      3369 8504 3365 8507 3363 8516 3362 8533

FLASH FLOOD...RADAR INDICATED

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 19, 9:37 PM EDTSpecial Weather StatementFFCCoweta53 min
Jul 19, 10:07 PM EDTFlash Flood WarningFFCCoweta, Heard, Troup6 hr
Jul 19, 10:13 PM EDTFlash Flood WarningFFCClayton, DeKalb, Fulton6 hr
Jul 19, 10:22 PM EDTRiver Flood WarningFFCDeKalb4 hr
Jul 19, 10:31 PM EDTRiver Flood WarningFFCDeKalb2 hr
Jul 19, 11:09 PM EDTRiver Flood WarningFFCDeKalb98 min
Jul 20, 3:21 AM EDTFlash Flood WatchFFCBanks, Barrow, Bartow, Carroll, Catoosa, Chattooga and 39 more19 hr
Jul 20, 1:45 PM EDTSpecial Weather StatementFFCHancock30 min
Jul 20, 3:54 PM EDTSpecial Weather StatementFFCNewton36 min
Jul 20, 4:22 PM EDTSpecial Weather StatementFFCMorgan23 min
Jul 20, 5:01 PM EDTSpecial Weather StatementFFCWilkes44 min
Jul 20, 5:40 PM EDTSpecial Weather StatementFFCMeriwether, Troup35 min
Jul 20, 5:55 PM EDTSpecial Weather StatementFFCBibb35 min
Jul 20, 7:41 PM EDTSpecial Weather StatementFFCLamar, Pike49 min
Jul 20, 7:57 PM EDTSpecial Weather StatementFFCJohnson48 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.