Alert archive / Georgia / Flash Flood Warnings in 2018

Flash Flood Warning 43, NWS Atlanta, GA

September 24, 2018Catoosa County, Whitfield County, Georgia

NWS Atlanta, GA issued this flash flood warning at Sep 24, 2018, 1:58 PM EDT for Catoosa County, Whitfield County, Georgia. It was in force for 6 hr. 3 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
Sep 24, 2018, 1:58 PM EDT (17:58 UTC)
Expired
Sep 24, 2018, 8:00 PM EDT
In force
6 hr
Issued by
NWS Atlanta, GA
Area
Storm-based polygon
Flood severity
None

Counties Catoosa County, GA, Whitfield County, GA

The radar

The Northeast Alabama radar (KHTX), 91 km from the middle of the area, began a volume at 17:59 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
Sep 24, 3:00 PM EDTFLASH FLOOD2 E Graysville, GAROAD CLOSED DUE TO FLOODING ON SWANSON RD AT INTERSECTION WITH HWY 151.
Sep 24, 3:00 PM EDTFLASH FLOOD2 Ese Boynton, GAHOLCOMB RD CLOSED IN TWO DIFFERENT LOCATIONS DUE TO FLOODING.
Sep 24, 3:00 PM EDTFLASH FLOOD2 Wsw Ringgold, GAROAD CLOSED DUE TO FLOODING ON POPLAR SPRINGS RD AT INTERSRCTION WITH BONNER RD.

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, 6.0 hours before the alert went out and 169 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 2018-09-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 209 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 12:00Z on 2018-09-24The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 28 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
209 J/kg
Mixed-layer CIN
-33 J/kg
Mixed-layer LCL
663 m above ground
0-6 km bulk shear
14 kt
0-1 km storm-relative helicity
28 m²/s²
0-3 km storm-relative helicity
52 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

429 
WGUS52 KFFC 241758
FFWFFC
GAC047-313-250000-
/O.NEW.KFFC.FF.W.0043.180924T1758Z-180925T0000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Peachtree City GA
158 PM EDT MON SEP 24 2018

The National Weather Service in Peachtree City has issued a

* Flash Flood Warning for...
  Catoosa County in northwestern Georgia...
  Central Whitfield County in northwestern Georgia...

* Until 800 PM EDT Monday.

* At 156 PM EDT, Doppler radar indicated heavy rain across the warned
  area. Up to three inches of rain have already fallen. Flash
  flooding is expected to begin shortly.

* Some locations that will experience flooding include...
  Dalton, Ringgold, Varnell, Tunnel Hill, Cohutta, Mill Creek, Wood 
  Station, Rocky Face, Graysville, Red Clay State Park, Indian 
  Springs and Apison.

Additional rainfall amounts up to two inches are possible in the 
warned area.

This includes the following streams and drainages...Little
Chickamauga Creek...Tiger Creek...Haig Mill Creek...Little Tiger
Creek...East Chickamauga Creek...Kenyon Creek...Hopkins Branch...
Hurricane Creek...Mill Creek...Drowning Bear Creek...Pitner Branch...
Dry Creek...Coahulla Creek...Tar Creek...Stone Branch...Johnson
Branch...Tanyard Creek...Peavine Creek...Peters Branch and Cat Creek.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Excessive runoff from heavy rainfall will cause flooding of small
creeks and streams, country roads, farmland, and other low lying
spots.

&&

LAT...LON 3478 8496 3473 8502 3473 8516 3476 8515
      3477 8515 3477 8516 3478 8516 3477 8520
      3480 8520 3499 8515 3499 8495

$$
1 follow-up statement
518 
WGUS72 KFFC 242351
FFSFFC

Flash Flood Statement
National Weather Service Peachtree City GA
751 PM EDT MON SEP 24 2018

GAC047-313-250000-
/O.EXP.KFFC.FF.W.0043.000000T0000Z-180925T0000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Catoosa GA-Whitfield GA-
751 PM EDT MON SEP 24 2018

...THE FLASH FLOOD WARNING FOR CATOOSA AND CENTRAL WHITFIELD COUNTIES
WILL EXPIRE AT 800 PM EDT...

The heavy rain has ended. Flooding is no longer expected to pose a
threat. Please continue to heed any remaining road closures.

LAT...LON 3478 8496 3473 8502 3473 8516 3476 8515
      3477 8515 3477 8516 3478 8516 3477 8520
      3480 8520 3499 8515 3499 8495

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 24, 10:52 AM EDTSpecial Weather StatementFFCCatoosa, Chattooga, Dade, Floyd, Walker, Whitfield53 min
Sep 24, 11:33 AM EDTFlash Flood WarningFFCChattooga, Floyd, Gordon, Walker6 hr
Sep 24, 1:06 PM EDTSpecial Weather StatementFFCCatoosa, Whitfield54 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.