Alert archive / Georgia / Flash Flood Warnings in 2021

Flash Flood Warning 2, NWS Greenville-Spartanburg, SC

March 31, 2021Oconee County, South Carolina; Habersham County, Rabun County, Georgia; Macon County, North Carolina

NWS Greenville-Spartanburg, SC issued this flash flood warning at Mar 31, 2021, 9:41 AM EDT for Oconee County, South Carolina; Habersham County, Rabun County, Georgia; Macon County, North Carolina. 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
Mar 31, 2021, 9:41 AM EDT (13:41 UTC)
Expired
Mar 31, 2021, 3:00 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, Macon County, NC, Oconee County, SC

The radar

The Greer radar (KGSP), 119 km from the middle of the area, began a volume at 13:42 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 12:00Z, 1.7 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 2021-03-31Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 111 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 2021-03-31The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 205 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
111 J/kg
Mixed-layer CIN
-58 J/kg
Mixed-layer LCL
562 m above ground
0-6 km bulk shear
47 kt
0-1 km storm-relative helicity
205 m²/s²
0-3 km storm-relative helicity
296 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

Open this sounding in Storm Lab

The text

As transmitted.

786 
WGUS52 KGSP 311341
FFWGSP
GAC137-241-NCC113-SCC073-311900-
/O.NEW.KGSP.FF.W.0002.210331T1341Z-210331T1900Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Greenville-Spartanburg SC
941 AM EDT Wed Mar 31 2021

The National Weather Service in Greenville-Spartanburg has issued a

* Flash Flood Warning for...
  Habersham County in northeastern Georgia...
  Rabun County in northeastern Georgia...
  Southeastern Macon County in western North Carolina...
  Northwestern Oconee County in upstate South Carolina...

* Until 300 PM EDT.

* At 941 AM EDT, Locally as much as 3 to 4 inches of rain is 
  expected to accumulate from around Lake Burton south to the 
  Batesville area, with an additional inch of rain likely to fall in 
  the Highway 441 corridor.

  HAZARD...Flash flooding caused by heavy rain.

  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...

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

&&

LAT...LON 3482 8365 3488 8366 3491 8363 3491 8360
      3494 8360 3495 8355 3499 8355 3501 8324
      3500 8309 3495 8312 3487 8325 3473 8335
      3468 8335 3449 8366 3451 8366 3454 8362
      3465 8366 3473 8362 3477 8363 3480 8368

FLASH FLOOD...RADAR AND GAUGE INDICATED

$$
2 follow-up statements
901 
WGUS72 KGSP 311540
FFSGSP

Flash Flood Statement
National Weather Service Greenville-Spartanburg SC
1140 AM EDT Wed Mar 31 2021

SCC073-311550-
/O.CAN.KGSP.FF.W.0002.000000T0000Z-210331T1900Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Oconee SC-
1140 AM EDT Wed Mar 31 2021

...FLASH FLOOD WARNING IS CANCELLED FOR NORTHWESTERN OCONEE COUNTY...

Flooding is no longer expected to pose a threat. Please continue to 
heed remaining road closures.

A Flash Flood Watch remains in effect until 800 PM EDT Wednesday for 
portions of northeast Georgia, western North Carolina and upstate 
South Carolina.

LAT...LON 3489 8364 3491 8360 3494 8360 3495 8355
      3499 8355 3501 8324 3500 8310 3499 8310
      3495 8312 3488 8324 3482 8331 3473 8335
      3468 8335 3463 8348 3454 8362 3465 8366
      3473 8362 3477 8363 3480 8368 3482 8365

$$

GAC137-241-NCC113-311900-
/O.CON.KGSP.FF.W.0002.000000T0000Z-210331T1900Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Habersham GA-Rabun GA-Macon NC-
1140 AM EDT Wed Mar 31 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 3 PM EDT THIS 
AFTERNOON FOR CENTRAL HABERSHAM, RABUN AND SOUTH CENTRAL MACON 
COUNTIES...

At 1140 AM EDT, doppler radar was showing that the threat of 
additional heavy rain had ended for time being.  Runoff from locally 
excessive rainfall this morning, as much as 3 inches in spots from 
Sky Valley to Lake Burton to Batesville, will continue to result in 
stream rises and flooding of low lying areas in the Upper Soque, 
Little Tennessee and North Georgia Power Reservoir system into this 
afternoon.

HAZARD...Flash flooding caused by thunderstorms.

SOURCE...Radar.

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...

In hilly terrain there are hundreds of low water crossings which are 
potentially dangerous in heavy rain. Do not attempt to cross flooded 
roads. Find an alternate route.

&&

LAT...LON 3489 8364 3491 8360 3494 8360 3495 8355
      3499 8355 3501 8324 3500 8310 3499 8310
      3495 8312 3488 8324 3482 8331 3473 8335
      3468 8335 3463 8348 3454 8362 3465 8366
      3473 8362 3477 8363 3480 8368 3482 8365

FLASH FLOOD...RADAR INDICATED

$$
369 
WGUS72 KGSP 311812
FFSGSP

Flash Flood Statement
National Weather Service Greenville-Spartanburg SC
212 PM EDT Wed Mar 31 2021

GAC137-241-NCC113-311900-
/O.CON.KGSP.FF.W.0002.000000T0000Z-210331T1900Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Habersham GA-Rabun GA-Macon NC-
212 PM EDT Wed Mar 31 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 3 PM EDT THIS 
AFTERNOON FOR NORTHERN HABERSHAM, RABUN AND SOUTHERN MACON 
COUNTIES...

At 212 PM EDT, Localized excessive runoff continued to diminish and 
no reports of flooding had been received, so this warning will 
expire on schedule.

HAZARD...Flash flooding caused by thunderstorms.

SOURCE...Radar.

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...

In hilly terrain there are hundreds of low water crossings which are 
potentially dangerous in heavy rain. Do not attempt to cross flooded 
roads. Find an alternate route.

&&

LAT...LON 3483 8360 3489 8350 3493 8348 3496 8350
      3499 8349 3501 8324 3500 8311 3499 8310
      3495 8312 3488 8324 3482 8331 3473 8335
      3468 8335 3467 8337 3461 8351 3473 8362
      3480 8363

FLASH FLOOD...RADAR INDICATED

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Mar 31, 4:25 AM EDTWind AdvisoryGSP43 hr
Mar 31, 10:14 AM EDTAreal Flood AdvisoryGSPOconee3 hr
Mar 31, 2:59 PM EDTFreeze WatchGSPAbbeville, Anderson, Cherokee, Chester, Greenwood, Laurens and 2 more12 hr
Mar 31, 8:55 AM EDTAreal Flood AdvisoryGSPHabersham, Rabun3 hr
Mar 31, 9:57 AM EDTFlash Flood WarningGSPRabun5 hr
Mar 31, 9:04 AM EDTAreal Flood AdvisoryGSPMacon3 hr
Mar 31, 9:23 AM EDTAreal Flood AdvisoryGSPGraham, Swain3 hr
Mar 31, 10:33 AM EDTAreal Flood AdvisoryGSPTransylvania4 hr
Mar 31, 1:03 PM EDTRiver Flood AdvisoryGSPHenderson, Transylvania14 hr
Mar 31, 2:04 PM EDTRiver Flood AdvisoryGSPBuncombe, Henderson13 hr
Mar 31, 2:23 PM EDTRiver Flood AdvisoryGSPBuncombe13 hr

Nearby

Flash Flood Warnings in Georgia, 2021Flash Flood Warnings in South Carolina, 2021Flash Flood Warnings in North Carolina, 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.