Alert archive / Georgia / Flash Flood Warnings in 2012

Flash Flood Warning 23, NWS Atlanta, GA

October 2, 2012White County, Georgia

NWS Atlanta, GA issued this flash flood warning at Oct 2, 2012, 2:49 AM EDT for White County, Georgia. It was in force for 5 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
Oct 2, 2012, 2:49 AM EDT (06:49 UTC)
Expired
Oct 2, 2012, 7:31 AM EDT
In force
5 hr
Issued by
NWS Atlanta, GA
Area
Storm-based polygon
Flood severity
None

County White County, GA

The radar

The Greer radar (KGSP), 136 km from the middle of the area, began a volume at 06:49 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
Oct 2, 3:00 AM EDTFLASH FLOOD1 W Helen, GAMINI COOPER DROVE INTO TWO FEET OF STANDING WATER ON HIGHWAY 17 JUST WEST OF HELEN. THE DRIVER HAD TO BE RESCUSED.

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, 6.8 hours before the alert went out and 162 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 2012-10-02Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 988 joules per kilogram.LCLEL10008507005003002001001 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 00:00Z on 2012-10-02The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 263 square meters per square second.19395878Sfc1 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
988 J/kg
Mixed-layer CIN
0 J/kg
Mixed-layer LCL
481 m above ground
0-6 km bulk shear
60 kt
0-1 km storm-relative helicity
263 m²/s²
0-3 km storm-relative helicity
292 m²/s²
Significant tornado parameter
1.8
Supercell composite
6.7

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

835 
WGUS52 KFFC 020649
FFWFFC
GAC311-021245-
/O.NEW.KFFC.FF.W.0023.121002T0649Z-121002T1245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
249 AM EDT TUE OCT 2 2012

THE NATIONAL WEATHER SERVICE IN PEACHTREE CITY HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  NORTHEASTERN WHITE COUNTY IN NORTHEAST GEORGIA

* UNTIL 845 AM EDT

* AT 239 AM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR AND RIVER
  GAGE READINGS INDICATED FLASH FLOODING FROM HEAVY RAINS OVER THE 
  WARNED AREA.

* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO UNICOI
  STATE PARK AND HELEN.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF SMALL
CREEKS AND STREAMS...AS WELL AS HIGHWAYS AND ROADS. ADDITIONALLY...
WOODLANDS AND FARMLANDS ALONG THE BANKS OF CREEKS...STREAMS AND 
OTHER LOW LYING AREAS ARE SUBJECT TO FLOODING.

FLOOD WATERS ARE MOVING DOWN CHATTAHOOCHEE RIVER NEAR AND THROUGH 
HELEN. AT 230 AM EDT THE RIVER LEVEL ON THE CHATTAHOOCHEE RIVER IN 
HELEN WAS 5.6 FEET AND RISING....FLOOD STAGE IS 6 FEET. THE RIVER 
SHOULD REACH FLOOD STAGE IN HELEN AROUND 300 AM EDT...CRESTING AROUND 
7 FEET EARLY TUESDAY MORNING. 

BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO RECOGNIZE THE
DANGERS OF FLOODING. IF FLASH FLOODING IS OBSERVED ACT QUICKLY. MOVE
UP TO HIGHER GROUND TO ESCAPE FLOOD WATERS. DO NOT STAY IN AREAS
SUBJECT TO FLOODING WHEN WATER BEGINS RISING.

IF YOU SEE SIGNIFICANT FLOODING CALL THE NATIONAL WEATHER SERVICE
TOLL FREE AT 1 8 6 6 7 6 3 4 4 6 6. YOU CAN ALSO TWEET YOUR REPORT
USING HASHTAG GAWX.

&&

LAT...LON 3479 8366 3477 8363 3468 8363 3466 8365
      3463 8363 3458 8363 3455 8361 3451 8366
      3451 8368 3454 8371 3470 8382 3478 8382
      3480 8376

$$
2 follow-up statements
125 
WGUS72 KFFC 021122
FFSFFC

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
722 AM EDT TUE OCT 2 2012

GAC311-021245-
/O.CON.KFFC.FF.W.0023.000000T0000Z-121002T1245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
WHITE GA-
722 AM EDT TUE OCT 2 2012

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 845 AM EDT FOR
NORTHEASTERN WHITE COUNTY...

THE RAIN HAS ENDED ACROSS WHITE COUNTY...HOWEVER RUNOFF FROM THE 
HEAVY RAIN OVERNIGHT CONTINUES TO PRODUCE FLOODING...MAINLY IN LOW 
LYING AREAS AND AROUND CREEKS AND STREAMS ACROSS NORTHEASTERN HALF 
OF THE COUNTY.

THE CHATTAHOOCHEE RIVER AT HELEN CRESTED JUST BELOW FLOOD STAGE 
EARLIER THIS MORNING AND IS NOW AT 4.1 FEET AND FALLING.

LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO UNICOI STATE
PARK AND HELEN

PRECAUTIONARY/PREPAREDNESS ACTIONS...

DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE
ROADWAY...THE WATER DEPTH MAY BE TOO GREAT TO ALLOW YOUR CAR TO CROSS
SAFELY. MOVE TO HIGHER GROUND.

DO NOT UNDERESTIMATE THE POWER OF FLOOD WATERS. ONLY A FEW INCHES OF
RAPIDLY FLOWING WATER CAN QUICKLY CARRY AWAY YOUR VEHICLE.

IF YOU SEE SIGNIFICANT FLOODING CALL THE NATIONAL WEATHER SERVICE
TOLL FREE AT 1 8 6 6 7 6 3 4 4 6 6. YOU CAN ALSO TWEET YOUR REPORT
USING HASHTAG GAWX.

&&

LAT...LON 3479 8366 3477 8363 3468 8363 3466 8365
      3463 8363 3458 8363 3455 8361 3451 8366
      3451 8368 3454 8371 3470 8382 3478 8382
      3480 8376

$$
391 
WGUS72 KFFC 021131
FFSFFC

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
731 AM EDT TUE OCT 2 2012

GAC311-021140-
/O.CAN.KFFC.FF.W.0023.000000T0000Z-121002T1245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
WHITE GA-
731 AM EDT TUE OCT 2 2012

...THE FLASH FLOOD WARNING HAS BEEN CANCELLED FOR NORTHEASTERN WHITE
COUNTY...

RUNOFF FROM OVERNIGHTS HEAVY RAINS HAS ENDED AND IS NO LONGER POSING 
A FLOODING PROBLEM. THEREFORE THE FLASH FLOOD WARNING FOR 
NORTHEASTERN WHITE COUNTY HAS BEEN CANCELLED.

IF YOU SEE SIGNIFICANT FLOODING CALL THE NATIONAL WEATHER SERVICE
TOLL FREE AT 1 8 6 6 7 6 3 4 4 6 6. YOU CAN ALSO TWEET YOUR REPORT
USING HASHTAG GAWX.

LAT...LON 3479 8366 3477 8363 3468 8363 3466 8365
      3463 8363 3458 8363 3455 8361 3451 8366
      3451 8368 3454 8371 3470 8382 3478 8382
      3480 8376

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Oct 1, 9:23 PM EDTFlash Flood WarningFFCHall6 hr
Oct 1, 10:17 PM EDTFlash Flood WarningFFCMeriwether, Pike, Spalding, Upson3 hr
Oct 1, 10:45 PM EDTSpecial Weather StatementFFCDeKalb, Gwinnett60 min
Oct 1, 10:54 PM EDTSpecial Weather StatementFFCDade36 min
Oct 1, 10:56 PM EDTFlash Flood WarningFFCDeKalb, Gwinnett6 hr
Oct 2, 1:18 AM EDTRiver Flood WarningFFCGwinnett3 hr
Oct 2, 1:18 AM EDTRiver Flood WarningFFCGwinnett6 hr
Oct 2, 4:10 AM EDTRiver Flood WarningFFCGwinnett, Walton6 hr
Oct 2, 6:41 AM EDTRiver Flood WarningFFCGwinnett18 hr
Oct 2, 11:26 AM EDTRiver Flood WarningFFCDeKalb, Rockdale8 hr

Nearby

Flash Flood Warnings in Georgia, 2012Every flash flood warning in 2012

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.