Alert archive / Georgia / Flash Flood Warnings in 2020

Flash Flood Warning 35, NWS Atlanta, GA

August 19, 2020Dade County, Georgia

NWS Atlanta, GA issued this flash flood warning at Aug 19, 2020, 2:08 PM EDT for Dade 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
Aug 19, 2020, 2:08 PM EDT (18:08 UTC)
Expired
Aug 19, 2020, 8:15 PM EDT
In force
6 hr
Issued by
NWS Atlanta, GA
Area
Storm-based polygon
Flood severity
None

County Dade County, GA

The radar

The Northeast Alabama radar (KHTX), 58 km from the middle of the area, began a volume at 18:10 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, 6.1 hours before the alert went out and 175 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 2020-08-19Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 691 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 2020-08-19The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -24 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
691 J/kg
Mixed-layer CIN
-94 J/kg
Mixed-layer LCL
1065 m above ground
0-6 km bulk shear
13 kt
0-1 km storm-relative helicity
-24 m²/s²
0-3 km storm-relative helicity
35 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

344 
WGUS52 KFFC 191808
FFWFFC
GAC083-200015-
/O.NEW.KFFC.FF.W.0035.200819T1808Z-200820T0015Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Peachtree City GA
208 PM EDT Wed Aug 19 2020

The National Weather Service in Peachtree City has issued a

* Flash Flood Warning for...
  Southwestern Dade County in northwestern Georgia...

* Until 815 PM EDT Wednesday.

* At 208 PM EDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 1 and 3 inches of rain 
  have fallen. Flash flooding is ongoing or expected to begin 
  shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  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...
  mainly rural areas of Southwestern Dade County

This includes the following streams and drainages...
  Mill Creek, Red River Branch, Long Branch and Lookout Creek.

Additional rainfall amounts of 1 to 2 inches are possible in the 
warned area.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

In hilly terrain there are hundreds of low water crossings which are 
potentially dangerous in heavy rain. Do not attempt to cross flooded 
roads. Find an alternate route.

&&

LAT...LON 3470 8549 3469 8549 3467 8551 3467 8554
      3469 8555 3470 8555 3471 8555 3472 8554
      3473 8553 3473 8552 3472 8551 3473 8549
      3472 8547 3471 8548

FLASH FLOOD...RADAR INDICATED

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 18, 9:38 PM EDTSpecial Weather StatementFFCClayton52 min
Aug 18, 9:42 PM EDTSevere Thunderstorm WarningFFCClayton, Coweta, Douglas, Fayette, Fulton36 min
Aug 18, 9:51 PM EDTSpecial Weather StatementFFCSumter24 min
Aug 19, 7:44 AM EDTSpecial Weather StatementFFCMurray31 min
Aug 19, 12:55 PM EDTSpecial Weather StatementFFCDade35 min
Aug 19, 1:32 PM EDTSpecial Weather StatementFFCDade, Walker28 min
Aug 19, 1:35 PM EDTSpecial Weather StatementFFCGilmer, Pickens25 min
Aug 19, 2:20 PM EDTSpecial Weather StatementFFCDawson25 min
Aug 19, 2:22 PM EDTSpecial Weather StatementFFCWhitfield38 min
Aug 19, 2:24 PM EDTSpecial Weather StatementFFCGilmer36 min
Aug 19, 2:37 PM EDTSevere Thunderstorm WarningFFCCatoosa, Whitfield23 min
Aug 19, 2:43 PM EDTSpecial Weather StatementFFCWhite32 min
Aug 19, 2:50 PM EDTSevere Thunderstorm WarningFFCMurray, Whitfield25 min
Aug 19, 3:11 PM EDTSevere Thunderstorm WarningFFCMurray, Whitfield34 min
Aug 19, 3:13 PM EDTSpecial Weather StatementFFCWhite32 min
Aug 19, 3:33 PM EDTSpecial Weather StatementFFCBartow27 min
Aug 19, 3:45 PM EDTSpecial Weather StatementFFCMurray30 min
Aug 19, 3:55 PM EDTSpecial Weather StatementFFCBartow, Floyd, Gordon35 min
Aug 19, 4:28 PM EDTSpecial Weather StatementFFCChattooga, Floyd, Gordon32 min
Aug 19, 5:09 PM EDTSpecial Weather StatementFFCCherokee36 min
Aug 19, 5:12 PM EDTSpecial Weather StatementFFCCarroll, Douglas33 min
Aug 19, 5:36 PM EDTSpecial Weather StatementFFCJackson24 min
Aug 19, 5:42 PM EDTSpecial Weather StatementFFCCarroll, Cherokee, Cobb, Douglas, Forsyth, Fulton33 min
Aug 19, 5:51 PM EDTSevere Thunderstorm WarningFFCCherokee, Cobb, Fulton28 min
Aug 19, 5:58 PM EDTSpecial Weather StatementFFCJackson32 min
Aug 19, 6:28 PM EDTSpecial Weather StatementFFCClarke32 min
Aug 19, 6:29 PM EDTSpecial Weather StatementFFCDeKalb, Fulton, Gwinnett31 min
Aug 19, 6:36 PM EDTSpecial Weather StatementFFCHeard24 min
Aug 19, 6:57 PM EDTSpecial Weather StatementFFCClarke33 min
Aug 19, 7:05 PM EDTSpecial Weather StatementFFCOconee25 min
Aug 19, 7:07 PM EDTSpecial Weather StatementFFCCoweta23 min
Aug 19, 7:08 PM EDTSpecial Weather StatementFFCGwinnett37 min
Aug 19, 7:18 PM EDTSpecial Weather StatementFFCGreene27 min
Aug 19, 7:22 PM EDTSpecial Weather StatementFFCWilkes23 min
Aug 19, 7:28 PM EDTSpecial Weather StatementFFCCoweta32 min
Aug 19, 7:45 PM EDTSpecial Weather StatementFFCGreene30 min
Aug 19, 7:47 PM EDTSpecial Weather StatementFFCWilkes28 min
Aug 19, 7:58 PM EDTSpecial Weather StatementFFCCoweta32 min

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.