Alert archive / Georgia / Flash Flood Warnings in 2018

Flash Flood Warning 32, NWS Atlanta, GA

July 31, 2018Polk County, Georgia

NWS Atlanta, GA issued this flash flood warning at Jul 31, 2018, 8:17 PM EDT for Polk County, Georgia. It was in force for 58 min. 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 31, 2018, 8:17 PM EDT (00:17 UTC)
Expired
Jul 31, 2018, 9:15 PM EDT
In force
58 min
Issued by
NWS Atlanta, GA
Area
Storm-based polygon
Flood severity
None

County Polk County, GA

The radar

The Atlanta radar (KFFC), 94 km from the middle of the area, began a volume at 00:19 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 00:00Z, 0.3 hours before the alert went out and 97 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 00:00Z on 2018-08-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 254 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 00:00Z on 2018-08-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 5 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
254 J/kg
Mixed-layer CIN
-34 J/kg
Mixed-layer LCL
637 m above ground
0-6 km bulk shear
24 kt
0-1 km storm-relative helicity
5 m²/s²
0-3 km storm-relative helicity
45 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

716 
WGUS52 KFFC 010017
FFWFFC
GAC233-010115-
/O.NEW.KFFC.FF.W.0032.180801T0017Z-180801T0115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Peachtree City GA
817 PM EDT TUE JUL 31 2018

The National Weather Service in Peachtree City has issued a

* Flash Flood Warning for...
  Polk County in northwestern Georgia...

* Until 915 PM EDT.

* At 815 PM EDT, Doppler radar and automated rain gauges indicated 
  thunderstorms producing heavy rain across the warned area. 
  Estimates of three to four inches of rain have fallen. Flash 
  flooding is expected to continue.

* Some locations that will experience flooding include...
  Cedartown, Rockmart, Aragon, Fish Creek, Etna, Esom Hill, Antioch
  and Van Wert.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Please report flooding to your local law enforcement agency when you
can do so safely.

&&

LAT...LON 3408 8542 3408 8526 3410 8526 3410 8516
      3408 8515 3408 8512 3410 8512 3410 8505
      3408 8505 3408 8492 3396 8498 3395 8505
      3392 8505 3393 8539

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 1, 1:41 AM EDTRiver Flood WarningFFCGwinnett10 hr
Aug 1, 1:36 PM EDTSpecial Weather StatementFFCTwiggs39 min
Aug 1, 2:15 PM EDTSpecial Weather StatementFFCBaldwin45 min
Aug 1, 2:48 PM EDTSpecial Weather StatementFFCToombs42 min
Aug 1, 4:03 PM EDTSpecial Weather StatementFFCJefferson27 min
Aug 1, 4:12 PM EDTSpecial Weather StatementFFCMadison33 min
Aug 1, 4:32 PM EDTSpecial Weather StatementFFCJefferson13 min
Aug 1, 7:18 PM EDTSpecial Weather StatementFFCOglethorpe, Taliaferro, Wilkes42 min
Aug 1, 7:21 PM EDTSpecial Weather StatementFFCOconee, Walton39 min
Aug 1, 7:24 PM EDTTornado WarningFFCMorgan, Newton, Walton36 min
Aug 1, 7:46 PM EDTRiver Flood WarningFFCGwinnett3 hr
Aug 1, 7:58 PM EDTSpecial Weather StatementFFCClarke, Oconee47 min

Nearby

Flash Flood Warnings in Georgia, 2018Every flash flood warning in 2018

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.