Alert archive / Georgia / Flash Flood Warnings in 2021

Flash Flood Warning 17, NWS Greenville-Spartanburg, SC

August 17, 2021Habersham County, Rabun County, Georgia

NWS Greenville-Spartanburg, SC issued this flash flood warning at Aug 17, 2021, 11:52 AM EDT for Habersham County, Rabun County, Georgia. It was in force for 5 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 17, 2021, 11:52 AM EDT (15:52 UTC)
Expired
Aug 17, 2021, 4:30 PM EDT
In force
5 hr
Issued by
NWS Greenville-Spartanburg, SC
Area
Storm-based polygon
Flood severity
None

Counties Habersham County, GA, Rabun County, GA

The radar

The Greer radar (KGSP), 116 km from the middle of the area, began a volume at 15:55 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
Aug 17, 1:30 PM EDTFLOOD1 Ese Sky Valley, GA911 CALL CENTER REPORTED MINOR FLOODING ON ROADWAYS SKY VALLEY WAY AND RIDGEPOLE DR.
Aug 17, 1:30 PM EDTFLASH FLOOD1 Sw Tiger, GA911 CALL CENTER REPORTED FLASH FLOOD ON SAGA MOUNTAIN RD NEAR TIGER CREEK

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, 3.9 hours before the alert went out and 184 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 2021-08-17Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 259 joules per kilogram.LCLEL10008507005003002001001 km2 km3 km6 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 2021-08-17The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 113 square meters per square second.193958Sfc1 km3 km6 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
259 J/kg
Mixed-layer CIN
0 J/kg
Mixed-layer LCL
461 m above ground
0-6 km bulk shear
11 kt
0-1 km storm-relative helicity
113 m²/s²
0-3 km storm-relative helicity
197 m²/s²
Significant tornado parameter
0.1
Supercell composite
0.8

Open this sounding in Storm Lab

The text

As transmitted.

052 
WGUS52 KGSP 171552
FFWGSP
GAC137-241-171900-
/O.NEW.KGSP.FF.W.0017.210817T1552Z-210817T1900Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Greenville-Spartanburg SC
1152 AM EDT Tue Aug 17 2021

The National Weather Service in Greenville-Spartanburg has issued a

* Flash Flood Warning for...
  Northern Habersham County in northeastern Georgia...
  Rabun County in northeastern Georgia...

* Until 300 PM EDT.

* At 1152 AM EDT, Doppler radar and automated rain gauges indicated 
  that widespread rainfall amounts of 2 to 3 inches have already 
  fallen across Rabun and Northern Habersham Counties since this 
  morning.  Widespread heavy tropical showers and embedded 
  thunderstorms will continue to develop across the region into 
  early afternoon. Flash flooding is ongoing or expected to begin 
  shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Radar and automated gauges.

  IMPACT...Flash flooding of small creeks and streams, urban
           areas, highways, streets and underpasses as well as
           other poor drainage and low-lying areas.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

When it is safe to do so, please report flooding or landslides 
threatening roads or property to the National Weather Service 
Greenville-Spartanburg by calling toll free, 1, 800, 2 6 7, 8 1 0 1, 
by posting on our Facebook page, or via Twitter using hashtag 
NWSGSP. Your message should describe the specific location where 
impacts occurred and the depth of flooding observed.

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

&&

LAT...LON 3486 8365 3490 8359 3494 8358 3494 8355
      3499 8354 3500 8311 3494 8313 3489 8324
      3480 8332 3473 8336 3469 8334 3463 8339
      3467 8351 3464 8358 3456 8362 3457 8363
      3466 8364 3474 8361 3479 8365

FLASH FLOOD...RADAR AND GAUGE INDICATED

$$
1 follow-up statement
620 
WGUS52 KGSP 171817
FFWGSP
GAC137-241-172030-
/O.EXT.KGSP.FF.W.0017.000000T0000Z-210817T2030Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Greenville-Spartanburg SC
217 PM EDT Tue Aug 17 2021

The National Weather Service in Greenville-Spartanburg has extended 
the

* Flash Flood Warning for...
  Northern Habersham County in northeastern Georgia...
  Rabun County in northeastern Georgia...

* Until 430 PM EDT.

* At 217 PM EDT, Rain gages across the warned area indicate that 
  widespread rainfall totals today have been 3 to 4 inches with the 
  threat of additional heavy rain showers ongoing.  Excessive runoff 
  will continue all afternoon across Rabun and adjacent areas of 
  Habersham County.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Radar and automated gauges.

  IMPACT...Flash flooding of small creeks and streams, urban
           areas, highways, streets and underpasses as well as
           other poor drainage and low-lying areas.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

When it is safe to do so, please report flooding or landslides 
threatening roads or property to the National Weather Service 
Greenville-Spartanburg by calling toll free, 1, 800, 2 6 7, 8 1 0 1, 
by posting on our Facebook page, or via Twitter using hashtag 
NWSGSP. Your message should describe the specific location where 
impacts occurred and the depth of flooding observed.

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

&&

LAT...LON 3486 8365 3490 8359 3494 8358 3494 8355
      3499 8354 3500 8311 3494 8313 3489 8324
      3480 8332 3473 8336 3469 8334 3463 8339
      3467 8351 3464 8358 3456 8362 3457 8363
      3466 8364 3474 8361 3479 8365

FLASH FLOOD...RADAR AND GAUGE INDICATED

$$

The office that day

Everything else NWS Greenville-Spartanburg, SC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 17, 10:23 AM EDTSpecial Weather StatementGSPElbert37 min
Aug 17, 10:36 AM EDTTornado WarningGSPHabersham39 min
Aug 17, 10:58 AM EDTTornado WarningGSPElbert, Hart26 min
Aug 17, 11:19 AM EDTSpecial Weather StatementGSPHabersham26 min
Aug 17, 11:29 AM EDTFlash Flood WarningGSPHabersham5 hr
Aug 17, 11:47 AM EDTTornado WarningGSPHabersham, Rabun, Stephens13 min
Aug 17, 1:58 PM EDTSpecial Weather StatementGSPRabun32 min
Aug 17, 2:31 PM EDTTornado WarningGSPRabun19 min
Aug 17, 4:28 PM EDTAreal Flood WarningGSPHabersham6 hr

Nearby

Flash Flood Warnings in Georgia, 2021Every flash flood warning in 2021

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.