Alert archive / Georgia / Flash Flood Warnings in 2018

Flash Flood Warning 41, NWS Atlanta, GA

September 18, 2018Emanuel County, Treutlen County, Georgia

NWS Atlanta, GA issued this flash flood warning at Sep 18, 2018, 4:27 AM EDT for Emanuel County, Treutlen County, Georgia. It was in force for 5 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
Sep 18, 2018, 4:27 AM EDT (08:27 UTC)
Expired
Sep 18, 2018, 9:15 AM EDT
In force
5 hr
Issued by
NWS Atlanta, GA
Area
Storm-based polygon
Flood severity
None

Counties Emanuel County, GA, Treutlen County, GA

The radar

The Robins AFB radar (KJGX), 95 km from the middle of the area, began a volume at 08:30 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

Jacksonville, FL (KJAX), launched 00:00Z, 8.5 hours before the alert went out and 216 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, Jacksonville, FL at 00:00Z on 2018-09-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2129 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, Jacksonville, FL at 00:00Z on 2018-09-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 56 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
2129 J/kg
Mixed-layer CIN
-11 J/kg
Mixed-layer LCL
1017 m above ground
0-6 km bulk shear
17 kt
0-1 km storm-relative helicity
56 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.

881 
WGUS52 KFFC 180827
FFWFFC
GAC107-283-181430-
/O.NEW.KFFC.FF.W.0041.180918T0827Z-180918T1430Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Peachtree City GA
427 AM EDT TUE SEP 18 2018

The National Weather Service in Peachtree City has issued a

* Flash Flood Warning for...
  South central Emanuel County in east central Georgia...
  Southern Treutlen County in east central Georgia...

* Until 1030 AM EDT Tuesday.

* At 426 AM EDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Two to four inches of rain have 
  already fallen and an additional one to two inches is possible. 
  Flash flooding is expected to begin shortly.

* Some locations that will experience flooding include...
  Soperton, Stillmore, Oak Park, Tarrytown, Lothair, Barnhill and
  Zaidee.

LAT...LON 3235 8225 3235 8224 3232 8223 3229 8228
      3229 8235 3232 8236 3235 8241 3231 8264
      3229 8267 3230 8271 3233 8275 3238 8272
      3244 8223 3241 8220

$$
1 follow-up statement
177 
WGUS72 KFFC 181315
FFSFFC

Flash Flood Statement
National Weather Service Peachtree City GA
915 AM EDT TUE SEP 18 2018

GAC107-283-181324-
/O.CAN.KFFC.FF.W.0041.000000T0000Z-180918T1430Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Emanuel GA-Treutlen GA-
915 AM EDT TUE SEP 18 2018

...THE FLASH FLOOD WARNING FOR SOUTH CENTRAL EMANUEL AND SOUTHERN
TREUTLEN COUNTIES IS CANCELLED...

Flood waters have receded and additional heavy rain is not expected. 
Flooding is no longer expected to pose a threat. 

LAT...LON 3235 8225 3235 8224 3232 8223 3229 8228
      3229 8235 3232 8236 3235 8241 3231 8264
      3229 8267 3230 8271 3233 8275 3238 8272
      3244 8223 3241 8220

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 17, 8:15 PM EDTSpecial Weather StatementFFCWilkinson30 min
Sep 18, 3:20 AM EDTSpecial Weather StatementFFCEmanuel40 min
Sep 18, 4:02 AM EDTSpecial Weather StatementFFCMontgomery, Treutlen28 min
Sep 18, 4:44 AM EDTSpecial Weather StatementFFCTelfair31 min
Sep 18, 5:17 AM EDTSpecial Weather StatementFFCWheeler28 min
Sep 18, 5:48 AM EDTSpecial Weather StatementFFCTelfair27 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.