Alert archive / Georgia / Flash Flood Warnings in 2017

Flash Flood Warning 38, NWS Atlanta, GA

August 4, 2017Bibb County, Georgia

NWS Atlanta, GA issued this flash flood warning at Aug 4, 2017, 8:40 PM EDT for Bibb 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: Aug 4, 2017, 8:40 PM EDT (00:40 UTC)
Expired: Aug 5, 2017, 2:45 AM EDT
In force: 6 hr
Issued by: NWS Atlanta, GA
Area: Storm-based polygon
Flood severity: None

County Bibb County, GA

The radar

The Robins AFB radar (KJGX), 38 km from the middle of the area, began a volume at 00:43 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

Time	Report	Where	Remark
Aug 4, 8:40 PM EDT	FLASH FLOOD	Ingleside, GA	STREET FLOODING WAS REPORTED ON VINEVILLE AVENUE AROUND PAYNE CITY.
Aug 4, 8:40 PM EDT	FLASH FLOOD	Wood Valley, GA	STREET FLOODING WAS REPORTED ON GRAY HIGHWAY. RADAR ESTIMATES NEAR 2 TO 2.5 INCHES.

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, 0.7 hours before the alert went out and 95 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 845 J/kg
Mixed-layer CIN: -9 J/kg
Mixed-layer LCL: 1238 m above ground
0-6 km bulk shear: 18 kt
0-1 km storm-relative helicity: 3 m²/s²
0-3 km storm-relative helicity: 21 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.1

Open this sounding in Storm Lab

The text

As transmitted.

020 
WGUS52 KFFC 050040
FFWFFC
GAC021-050645-
/O.NEW.KFFC.FF.W.0038.170805T0040Z-170805T0645Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Peachtree City GA
840 PM EDT FRI AUG 4 2017

The National Weather Service in Peachtree City has issued a

* Flash Flood Warning for...
  Bibb County in central Georgia...

* Until 245 AM EDT Saturday

* At 839 PM EDT, Doppler radar indicated thunderstorms producing
  heavy rain across the warned area. Flash flooding is expected to
  begin shortly.

Additional rainfall amounts of 1 inch are possible in the warned 
area. Rainfall amounts of up to 2.5 inches has already occurred. 
This additional rainfall will likely cause flash flooding.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Excessive runoff from heavy rainfall will cause flooding of small
creeks and streams, urban areas, highways, streets and underpasses as
well as other drainage areas and low lying spots.

If you see significant flooding call the National Weather Service
toll free at 1 8 6 6 7 6 3 4 4 6 6 or tweet us your report at
NWSATLANTA.

&&

LAT...LON 3273 8380 3277 8384 3280 8386 3283 8390
      3287 8386 3293 8370 3292 8370 3289 8366
      3289 8360 3287 8358 3287 8357 3278 8353
      3275 8356 3271 8376

$$

1 follow-up statement

913 
WGUS72 KFFC 050206
FFSFFC

Flash Flood Statement
National Weather Service Peachtree City GA
1006 PM EDT FRI AUG 4 2017

GAC021-050216-
/O.CAN.KFFC.FF.W.0038.000000T0000Z-170805T0645Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Bibb GA-
1006 PM EDT FRI AUG 4 2017

...THE FLASH FLOOD WARNING FOR BIBB COUNTY IS CANCELLED...

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

LAT...LON 3273 8380 3277 8384 3280 8386 3283 8390
      3287 8386 3293 8370 3292 8370 3289 8366
      3289 8360 3287 8358 3287 8357 3278 8353
      3275 8356 3271 8376

$$

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 4, 8:22 PM EDT	Special Weather Statement	FFC	Bibb	53 min
Aug 4, 8:23 PM EDT	Special Weather Statement	FFC	Talbot	67 min
Aug 4, 8:27 PM EDT	Severe Thunderstorm Warning	FFC	Catoosa, Dade, Walker, Whitfield	48 min
Aug 4, 8:37 PM EDT	Severe Thunderstorm Warning	FFC	Baldwin, Twiggs, Wilkinson	38 min
Aug 4, 8:42 PM EDT	Special Weather Statement	FFC	Jackson	48 min
Aug 4, 8:53 PM EDT	Tornado Warning	FFC	Wilkinson	52 min
Aug 4, 8:59 PM EDT	Special Weather Statement	FFC	Towns, Union	46 min
Aug 4, 9:36 PM EDT	Special Weather Statement	FFC	Washington	39 min
Aug 4, 9:42 PM EDT	Special Weather Statement	FFC	Barrow, Jackson	48 min
Aug 4, 9:57 PM EDT	Special Weather Statement	FFC	Whitfield	48 min
Aug 5, 12:46 AM EDT	Special Weather Statement	FFC	Coweta, Fayette	44 min
Aug 5, 7:33 PM EDT	Special Weather Statement	FFC	Hancock	42 min

Nearby

Flash Flood Warnings in Georgia, 2017 Every flash flood warning in 2017

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.