Alert archive / Georgia / Flash Flood Warnings in 2018

Flash Flood Warning 4, NWS Atlanta, GA

May 18, 2018Murray County, Whitfield County, Georgia

NWS Atlanta, GA issued this flash flood warning at May 18, 2018, 11:23 PM EDT for Murray County, Whitfield 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
May 18, 2018, 11:23 PM EDT (03:23 UTC)
Expired
May 19, 2018, 5:15 AM EDT
In force
6 hr
Issued by
NWS Atlanta, GA
Area
Storm-based polygon
Flood severity
None

Counties Murray County, GA, Whitfield County, GA

The radar

The Northeast Alabama radar (KHTX), 125 km from the middle of the area, began a volume at 03:27 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 18, 11:30 PM EDTFLASH FLOODChatsworth, GANUMEROUS REPORTS REGARDING STREET FLOODING ESPECIALLY IN CHATSWORTH BUT EXTENDING ALONG MUCH OF HWY 411 THRU THE COUNTY. SEVERAL FLOODED ROADWAYS INCLUDE: HWY 411 NEAR INTERSECTION OF W CHESTNUT ST, FORT MOUNTAIN DRIVE, MISTY VALLEY DRIVE AND AREAS NORTH OF CH

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 00:00Z, 3.4 hours before the alert went out and 150 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 2018-05-19Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 660 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 2018-05-19The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 39 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
660 J/kg
Mixed-layer CIN
-21 J/kg
Mixed-layer LCL
1014 m above ground
0-6 km bulk shear
15 kt
0-1 km storm-relative helicity
39 m²/s²
0-3 km storm-relative helicity
82 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

394 
WGUS52 KFFC 190323
FFWFFC
GAC213-313-190915-
/O.NEW.KFFC.FF.W.0004.180519T0323Z-180519T0915Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Peachtree City GA
1123 PM EDT FRI MAY 18 2018

The National Weather Service in Peachtree City has issued a

* Flash Flood Warning for...
  Murray County in northwestern Georgia...
  Eastern Whitfield County in northwestern Georgia...

* Until 515 AM EDT.

* At 1122 PM EDT, Doppler radar indicated thunderstorms producing
  heavy rain across the warned area. Up to two inches of rain have
  already fallen. Flash flooding is expected.

* Some locations that will experience flooding include...
  Dalton, Chatsworth, Eton, Crandall, Carters, Sumac, Ramhurst,
  Gregory, Tilton, Conasauga Lake, Beaverdale, Dawnville, Cisco, Fort
  Mountain State Park and North Georgia Speedway.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Be especially cautious at night when it is harder to recognize the
dangers of flooding.

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 3497 8462 3485 8462 3475 8464 3473 8466
      3469 8466 3459 8468 3460 8473 3461 8473
      3461 8472 3462 8472 3462 8474 3461 8475
      3461 8480 3463 8488 3463 8492 3464 8500
      3498 8486

$$

The office that day

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

IssuedProductOfficeCountiesLasted
May 18, 10:45 PM EDTSpecial Weather StatementFFCBartow, Gordon, Murray, Polk30 min
May 18, 11:15 PM EDTSpecial Weather StatementFFCBartow, Gordon, Murray, Polk30 min
May 18, 11:45 PM EDTSpecial Weather StatementFFCGordon30 min
May 19, 12:04 AM EDTFlash Flood WarningFFCBartow, Floyd, Gordon6 hr
May 19, 9:15 AM EDTRiver Flood WarningFFCMurray, Whitfield30 hr
May 19, 11:16 AM EDTRiver Flood WarningFFCGordon11 hr
May 19, 5:38 PM EDTSpecial Weather StatementFFCStewart22 min
May 19, 6:51 PM EDTSpecial Weather StatementFFCWheeler24 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.