Alert archive / Georgia / Flash Flood Warnings in 2018

Flash Flood Warning 3, NWS Atlanta, GA

May 16, 2018Cobb County, Douglas County, Fulton County, Georgia

NWS Atlanta, GA issued this flash flood warning at May 16, 2018, 9:31 AM EDT for Cobb County, Douglas County, Fulton County, Georgia. It was in force for 6 hr. 2 reports 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
May 16, 2018, 9:31 AM EDT (13:31 UTC)
Expired
May 16, 2018, 3:30 PM EDT
In force
6 hr
Issued by
NWS Atlanta, GA
Area
Storm-based polygon
Flood severity
None

Counties Cobb County, GA, Douglas County, GA, Fulton County, GA

The radar

The Atlanta radar (KFFC), 48 km from the middle of the area, began a volume at 13:34 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
May 16, 10:26 AM EDTFLASH FLOOD1 E Lithia Springs, GADOUGLAS COUNTY DOT CLOSED MT. VERNON ROAD AT WOODROW WILSON PARK IN LITHIA SPRINGS DUE TO FLOODING.
May 16, 11:22 AM EDTFLASH FLOODLithia Springs, GAMARSH AVENUE CLOSED DUE TO FLOODING.

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, 1.5 hours before the alert went out and 49 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 2018-05-16Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 283 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°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 2018-05-16The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -53 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
283 J/kg
Mixed-layer CIN
-1 J/kg
Mixed-layer LCL
478 m above ground
0-6 km bulk shear
4 kt
0-1 km storm-relative helicity
-53 m²/s²
0-3 km storm-relative helicity
-19 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

979 
WGUS52 KFFC 161331
FFWFFC
GAC067-097-121-161930-
/O.NEW.KFFC.FF.W.0003.180516T1331Z-180516T1930Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Peachtree City GA
931 AM EDT WED MAY 16 2018

The National Weather Service in Peachtree City has issued a

* Flash Flood Warning for...
  Southern Cobb County in north central Georgia...
  Northeastern Douglas County in north central Georgia...
  Southwestern Fulton County in north central Georgia...

* Until 330 PM EDT Wednesday.

* At 928 AM EDT, Doppler radar and automated rain gauges indicated
  heavy rain falling across the warned area. Up to two inches of 
  rain have already fallen. An additional one to two inches is 
  possible in the next hour or two. Flash flooding is expected to 
  begin shortly.

* Some locations that will experience flooding include...
  Atlanta, Douglasville, Smyrna, Powder Springs, Austell, Lithia
  Springs, Sweetwater Creek State Park, Jim R Miller Park, Chapel
  Hill, Six Flags Over Georgia, Campbellton, Bolton, Mableton and 
  Vinings. This warning also includes portions of the Chattahoochee 
  River and associated tributaries.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

A Flash Flood Warning means that flooding is imminent or occurring.
If you are in the warned area move to higher ground immediately.
Residents living along streams and creeks should take immediate
precautions to protect life and property.

&&

LAT...LON 3379 8474 3379 8472 3380 8472 3391 8460
      3382 8443 3364 8468 3374 8480

$$
1 follow-up statement
008 
WGUS72 KFFC 161926
FFSFFC

Flash Flood Statement
National Weather Service Peachtree City GA
326 PM EDT WED MAY 16 2018

GAC067-097-121-161935-
/O.EXP.KFFC.FF.W.0003.000000T0000Z-180516T1930Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Cobb GA-Douglas GA-Fulton GA-
326 PM EDT WED MAY 16 2018

...THE FLASH FLOOD WARNING FOR SOUTHERN COBB...NORTHEASTERN DOUGLAS
AND SOUTHWESTERN FULTON COUNTIES WILL EXPIRE AT 330 PM EDT...

The heavy rain has ended. Flood waters have receded. Flooding is no 
longer expected to pose a threat. Additional rainfall amounts are 
possible this afternoon and evening and over the next several 
days.

LAT...LON 3379 8474 3379 8472 3380 8472 3391 8460
      3382 8443 3364 8468 3374 8480

$$

The office that day

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

IssuedProductOfficeCountiesLasted
May 16, 8:07 AM EDTSpecial Weather StatementFFCCobb, Douglas53 min
May 16, 8:35 AM EDTSpecial Weather StatementFFCCarroll40 min
May 16, 9:00 AM EDTSpecial Weather StatementFFCDouglas, Fulton, Gwinnett60 min
May 16, 9:19 AM EDTSpecial Weather StatementFFCCarroll41 min
May 16, 9:40 AM EDTRiver Flood WarningFFCGwinnett74 min
May 16, 9:59 AM EDTSpecial Weather StatementFFCBanks, Cobb, Forsyth, Hall61 min
May 16, 10:09 AM EDTRiver Flood WarningFFCCobb, Douglas3 hr
May 16, 10:14 AM EDTRiver Flood WarningFFCFulton, Gwinnett98 min
May 16, 10:16 AM EDTSpecial Weather StatementFFCDouglas44 min
May 16, 10:42 AM EDTSpecial Weather StatementFFCChattahoochee, Lamar, Marion, Monroe, Stewart, Talbot and 3 more48 min
May 16, 10:56 AM EDTSpecial Weather StatementFFCDeKalb, Fulton49 min
May 16, 11:27 AM EDTSpecial Weather StatementFFCButts, Jasper, Lamar, Marion, Monroe, Newton and 5 more48 min
May 16, 12:46 PM EDTSpecial Weather StatementFFCPeach44 min
May 16, 12:50 PM EDTSpecial Weather StatementFFCWalton25 min
May 16, 12:55 PM EDTSpecial Weather StatementFFCWebster35 min
May 16, 1:23 PM EDTSpecial Weather StatementFFCMacon, Peach52 min
May 16, 1:26 PM EDTSpecial Weather StatementFFCJasper34 min
May 16, 2:29 PM EDTSpecial Weather StatementFFCBibb, Dooly, Houston, Peach, Sumter46 min
May 16, 2:34 PM EDTSpecial Weather StatementFFCGreene, Oglethorpe41 min
May 16, 3:18 PM EDTSpecial Weather StatementFFCCrisp, Dooly, Houston, Pulaski, Twiggs27 min
May 16, 3:54 PM EDTSpecial Weather StatementFFCMontgomery, Telfair, Toombs, Wheeler51 min
May 16, 3:59 PM EDTSpecial Weather StatementFFCCrisp31 min
May 16, 4:33 PM EDTSpecial Weather StatementFFCEmanuel27 min
May 16, 5:01 PM EDTSpecial Weather StatementFFCCrisp, Dodge, Telfair, Wilcox29 min
May 16, 5:33 PM EDTSpecial Weather StatementFFCBleckley, Dodge, Pulaski27 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.