Alert archive / Georgia / Flash Flood Warnings in 2009

Flash Flood Warning 42, NWS Atlanta, GA

September 21, 20094 counties in Georgia

NWS Atlanta, GA issued this flash flood warning at Sep 21, 2009, 11:32 PM EDT for 4 counties in 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 21, 2009, 11:32 PM EDT (03:32 UTC)
Expired
Sep 22, 2009, 5:00 AM EDT
In force
5 hr
Issued by
NWS Atlanta, GA
Area
Storm-based polygon
Flood severity
None

Counties Dooly County, GA, Houston County, GA, Macon County, GA, Peach County, GA

The radar

The Robins AFB radar (KJGX), 68 km from the middle of the area, began a volume at 03:34 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.

The nearest sounding before it

Peachtre/Fal Fld, GA (KFFC), launched 00:00Z, 3.5 hours before the alert went out and 127 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 2009-09-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 835 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 00:00Z on 2009-09-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 72 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
835 J/kg
Mixed-layer CIN
-42 J/kg
Mixed-layer LCL
624 m above ground
0-6 km bulk shear
24 kt
0-1 km storm-relative helicity
72 m²/s²
0-3 km storm-relative helicity
73 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.2

Open this sounding in Storm Lab

The text

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

000 
WGUS52 KFFC 220332
FFWFFC
GAC093-153-193-225-220900-
/O.NEW.KFFC.FF.W.0042.090922T0332Z-090922T0900Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
1132 PM EDT MON SEP 21 2009

THE NATIONAL WEATHER SERVICE IN PEACHTREE CITY HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  DOOLY COUNTY IN CENTRAL GEORGIA
  SOUTHERN HOUSTON COUNTY IN CENTRAL GEORGIA
  SOUTHERN PEACH COUNTY IN CENTRAL GEORGIA
  MACON COUNTY IN WEST CENTRAL GEORGIA

* UNTIL 500 AM EDT TUESDAY

* AT 1130 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED 
AN AREA OF INTENSE THUNDERSTORMS CONTAINING VERY HEAVY RAIN ACROSS 
HOUSTON...DOOLY AND MACON COUNTIES. THIS AREA WAS MOVING SLOWLY 
SOUTH AT 5 MPH. RAINFALL AMOUNTS OF 1 TO 3 INCHES HAS ALREADY FALLEN 
IN THIS AREA AND AN ADDITIONAL 1 TO 2 INCHES CAN BE EXPECTED THROUGH 
1 AM. ALTHOUGH THE RAIN MAY TAPER OFF BY 1 AM...RUNOFF FROM THE VERY 
HEAVY RAIN WILL LEAD TO FLASH FLOODING OF CREEKS AND STREAMS AS WELL 
AS LOW LYING AND POOR DRAINAGE AREAS THROUGH THE EARLY MORNING 
HOURS. 

* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO PERRY...  
MARSHALLVILLE...FORT VALLEY...OGLETHORPE AND UNADILLA.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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...MOVE TO A SAFE AREA THEN CALL THE 
NATIONAL WEATHER SERVICE TOLL FREE AT 1 8 6 6 7 6 3 4 4 6 6.

&&

LAT...LON 3214 8402 3218 8404 3218 8412 3222 8413
      3223 8421 3229 8421 3230 8425 3237 8425
      3241 8418 3249 8412 3252 8405 3249 8401
      3259 8390 3251 8352 3243 8348 3240 8348
      3229 8362 3225 8360 3206 8378

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 21, 8:40 PM EDTFlash Flood WarningFFCBaldwin, Greene, Hancock, Jasper, Jones, Morgan and 5 more6 hr
Sep 21, 9:07 PM EDTAreal Flood WarningFFCCarroll, Cherokee, Cobb, Coweta, DeKalb, Douglas and 6 more18 hr
Sep 21, 9:48 PM EDTAreal Flood WarningFFCCatoosa, Chattooga, Dade, Murray, Walker, Whitfield12 hr
Sep 21, 10:11 PM EDTFlash Flood WarningFFCBibb, Houston, Peach, Twiggs6 hr
Sep 21, 10:34 PM EDTRiver Flood WarningFFCBaldwin, Washington, Wilkinson18 hr
Sep 21, 11:56 PM EDTRiver Flood WarningFFCBartow, Floyd11 hr
Sep 22, 7:04 AM EDTRiver Flood WarningFFCDeKalb, Rockdale40 hr
Sep 22, 7:04 AM EDTRiver Flood WarningFFCNewton, Rockdale51 hr
Sep 22, 7:04 AM EDTRiver Flood WarningFFCWhitfield51 hr
Sep 22, 7:04 AM EDTRiver Flood WarningFFCPutnam8 hr
Sep 22, 9:26 AM EDTRiver Flood WarningFFCMurray, Whitfield15 hr
Sep 22, 9:26 AM EDTRiver Flood WarningFFCBarrow, Jackson14 hr
Sep 22, 9:43 AM EDTAreal Flood WarningFFCCatoosa, Chattooga, Dade, Murray, Walker, Whitfield24 hr
Sep 22, 12:05 PM EDTAreal Flood WarningFFCDooly6 hr
Sep 22, 1:52 PM EDTRiver Flood WarningFFCClayton, Fayette, Spalding9 hr
Sep 22, 2:29 PM EDTAreal Flood WarningFFCCarroll, Cherokee, Cobb, Coweta, DeKalb, Douglas and 6 more18 hr
Sep 22, 5:54 PM EDTRiver Flood WarningFFCDooly18 hr

Nearby

Flash Flood Warnings in Georgia, 2009Every flash flood warning in 2009

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.