Alert archive / North Carolina / Flash Flood Warnings in 2021

Flash Flood Warning 32, NWS Greenville-Spartanburg, SC

August 17, 2021Avery County, Burke County, Caldwell County, North Carolina

NWS Greenville-Spartanburg, SC issued this flash flood warning at Aug 17, 2021, 6:00 PM EDT for Avery County, Burke County, Caldwell County, North Carolina. It was in force for 9 hr. 1 report 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, 6:00 PM EDT (22:00 UTC)
Expired
Aug 18, 2021, 2:49 AM EDT
In force
9 hr
Issued by
NWS Greenville-Spartanburg, SC
Area
Storm-based polygon
Flood severity
None

Counties Avery County, NC, Burke County, NC, Caldwell County, NC

The radar

The Greer radar (KGSP), 127 km from the middle of the area, began a volume at 22:04 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, 10:17 PM EDTFLOOD1 Wnw Collettsville, NCJOHNS RIVER ROAD AT HWY 90 IMPASSABLE DUE TO RIVER OVERFLOW

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Greensboro/Hi Pt, NC (KGSO), launched 12:00Z, 10.0 hours before the alert went out and 179 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, Greensboro/Hi Pt, NC at 12:00Z on 2021-08-17Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 522 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, Greensboro/Hi Pt, NC at 12:00Z on 2021-08-17The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 77 square meters per square second.193958Sfc1 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
522 J/kg
Mixed-layer CIN
-5 J/kg
Mixed-layer LCL
593 m above ground
0-6 km bulk shear
26 kt
0-1 km storm-relative helicity
77 m²/s²
0-3 km storm-relative helicity
99 m²/s²
Significant tornado parameter
0.1
Supercell composite
0.9

Open this sounding in Storm Lab

The text

As transmitted.

208 
WGUS52 KGSP 172200
FFWGSP
NCC011-023-027-180200-
/O.NEW.KGSP.FF.W.0032.210817T2200Z-210818T0200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

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

The National Weather Service in Greenville-Spartanburg has issued a

* Flash Flood Warning for...
  Avery County in western North Carolina...
  Northwestern Burke County in western North Carolina...
  Northwestern Caldwell County in western North Carolina...

* Until 1000 PM EDT.

* At 600 PM EDT, As heavy tropical-like thunderstorms continue to 
  develop across the warned area this evening, rainfall totals near 
  favored elevated locales may top out at 5 or 6 inches.  Developing 
  flooding of streams and eventually larger rivers in the area is 
  likely as the evening wears on.

  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.

* Some locations that will experience flash flooding include...
  Newland, Blowing Rock In Caldwell County, Banner Elk, Elk Park, 
  Beech Mountain In Avery County, Crossnore, Sugar Mountain, Seven 
  Devils, B.R. Parkway-Linville Falls To Grandfather, Linville 
  Falls, Grandfather Mountain State Park, Table Rock, B.R. 
  Parkway-Little Switzerland To Linville, Lake James State Park, 
  Lake James, Edgemont, Jonas Ridge, Pineola, Linville and Globe.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3591 8198 3596 8204 3601 8203 3610 8208
      3611 8203 3628 8192 3621 8191 3619 8189
      3619 8186 3611 8181 3612 8163 3595 8158
      3580 8169 3576 8177 3574 8189 3581 8198
      3583 8192 3589 8189 3595 8192 3596 8194

FLASH FLOOD...RADAR INDICATED

$$
2 follow-up statements
191 
WGUS52 KGSP 180132
FFWGSP
NCC011-023-027-180700-
/O.EXT.KGSP.FF.W.0032.000000T0000Z-210818T0700Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

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

The National Weather Service in Greenville-Spartanburg has extended 
the

* Flash Flood Warning for...
  Avery County in western North Carolina...
  Northwestern Burke County in western North Carolina...
  Northwestern Caldwell County in western North Carolina...

* Until 300 AM EDT.

* At 932 PM EDT, Storm-total rainfall of 2-5 inches has occurred 
  across Avery, Burke, and Caldwell counties.  The heavy rainfall 
  has left Avery and Burke counties, with no additional rainfall 
  expected.  Heavy rainfall will continue across central and eastern 
  Caldwell County over the next 60 minutes with flash flooding 
  developing from Edgemont to Collettsville along the headwaters of 
  Johns River, Mulberry Creek, and Wilson Creek.

* Avery County Emergency Management is currently conducting 
  evacuations of low-lying areas.  Moderate flooding of the North 
  Toe River near Newland is ongoing, which will cause flooding to 
  some structures near the river as well as extensive flooding of 
  low-lying areas including adjacent campgrounds.  Residents near 
  the North Toe River, Linville River, and Wilson Creek, as well as 
  all other streams across Avery, Burke, and Caldwell counties are 
  urged to seek higher ground immediately.

  HAZARD...Life threatening flash flooding. Thunderstorms
           producing flash flooding.

  SOURCE...Emergency management reported.

  IMPACT...Life threatening flash flooding of creeks and streams,
           urban areas, highways, streets and underpasses.
           Significant flooding of campgrounds near streams is
           expected.  Some structural flooding is likely.  A few
           landslides are also possible.

* Some locations that may continue to experience flash flooding 
  include...
  Newland, Blowing Rock In Caldwell County, Banner Elk, Elk Park, 
  Beech Mountain In Avery County, Crossnore, Sugar Mountain, Seven 
  Devils, Linville Falls, Table Rock, Lake James State Park, Lake 
  James, Edgemont, Jonas Ridge, Pineola, Linville and Globe.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Heavy rain is increasing the risk of landslides, especially in areas 
where slides have occurred in the past. Be especially alert if you 
are near a stream, especially at the base of a mountain or in a 
cove. Watch for loose-moving soil and rocks or a sudden increase in 
streamflow. Leave the area quickly if this is observed. When driving 
along roads where the terrain is steep or rocky, watch and listen 
for falling rocks, mud, trees and other debris.

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

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 3591 8198 3596 8204 3601 8203 3610 8208
      3611 8203 3628 8192 3621 8191 3619 8189
      3619 8186 3611 8181 3612 8163 3595 8158
      3580 8169 3576 8177 3574 8189 3581 8198
      3583 8192 3589 8189 3595 8192 3596 8194

FLASH FLOOD...OBSERVED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE
EXPECTED RAINFALL...1 INCH IN 1 HOUR

$$

JMP
534 
WGUS72 KGSP 180649
FFSGSP

Flash Flood Statement
National Weather Service Greenville-Spartanburg SC
249 AM EDT Wed Aug 18 2021

NCC011-023-027-180658-
/O.CAN.KGSP.FF.W.0032.000000T0000Z-210818T0700Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Caldwell NC-Avery NC-Burke NC-
249 AM EDT Wed Aug 18 2021

...THE FLASH FLOOD WARNING FOR NORTHWESTERN CALDWELL...AVERY AND
NORTHWESTERN BURKE COUNTIES IS CANCELLED...

Flash flooding has ended, but elevated river levels remain. 
Therefore, the Flash Flood Warning has been replaced by a Flood 
Advisory in Avery County and a Flood Warning in Caldwell and Burke 
counties.  Please continue to heed all evacuation orders and 
barricades until officials have determined it is safe to return.

LAT...LON 3591 8198 3596 8204 3601 8203 3610 8208
      3611 8203 3628 8192 3621 8191 3619 8189
      3619 8186 3611 8181 3612 8163 3595 8158
      3580 8169 3576 8177 3574 8189 3581 8198
      3583 8192 3589 8189 3595 8192 3596 8194

$$

JMP

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 17, 2:22 AM EDTRiver Flood WarningGSPHenderson, Transylvania4 days
Aug 17, 3:01 AM EDTRiver Flood AdvisoryGSPBuncombe, Henderson79 min
Aug 17, 3:27 AM EDTRiver Flood AdvisoryGSPBuncombe26 hr
Aug 17, 3:59 AM EDTRiver Flood WarningGSPMadison40 hr
Aug 17, 4:12 AM EDTRiver Flood WarningGSPBuncombe31 hr
Aug 17, 4:20 AM EDTRiver Flood WarningGSPBuncombe, Henderson4 days
Aug 17, 11:36 AM EDTTornado Warning Tornado observedGSPAlexander, Iredell39 min
Aug 17, 12:05 PM EDTSpecial Weather StatementGSPIredell25 min
Aug 17, 12:06 PM EDTTornado WarningGSPIredell39 min
Aug 17, 12:33 PM EDTTornado WarningGSPAlexander12 min
Aug 17, 12:42 PM EDTTornado Warning Tornado observedGSPIredell18 min
Aug 17, 1:09 PM EDTFlash Flood WarningGSPJackson, Macon, Transylvania5 hr
Aug 17, 1:25 PM EDTFlash Flood WarningGSPTransylvania4 hr
Aug 17, 1:56 PM EDTSpecial Weather StatementGSPTransylvania34 min
Aug 17, 2:01 PM EDTSpecial Weather StatementGSPCatawba, Lincoln29 min
Aug 17, 2:02 PM EDTSpecial Weather StatementGSPIredell28 min
Aug 17, 2:02 PM EDTSpecial Weather StatementGSPAlexander28 min
Aug 17, 2:31 PM EDTTornado WarningGSPBurke, Caldwell44 min
Aug 17, 2:31 PM EDTTornado WarningGSPMacon19 min
Aug 17, 3:02 PM EDTTornado WarningGSPCaldwell43 min
Aug 17, 3:06 PM EDTTornado WarningGSPAlexander, Caldwell39 min
Aug 17, 3:12 PM EDTFlash Flood WarningGSPHaywood3 hr
Aug 17, 3:41 PM EDTFlash Flood WarningGSPBuncombe5 hr
Aug 17, 3:48 PM EDTTornado WarningGSPAlexander, Burke, Caldwell, Catawba42 min
Aug 17, 4:07 PM EDTTornado WarningGSPAvery, Burke, McDowell, Mitchell53 min
Aug 17, 4:08 PM EDTFlash Flood WarningGSPMadison9 hr
Aug 17, 4:16 PM EDTFlash Flood WarningGSPBuncombe, Henderson5 hr
Aug 17, 4:17 PM EDTTornado WarningGSPAvery, Burke, Caldwell43 min
Aug 17, 4:20 PM EDTTornado WarningGSPHenderson, Polk, Rutherford12 min
Aug 17, 4:24 PM EDTFlash Flood Warning Considerable damage threatGSPHaywood4 hr
Aug 17, 4:35 PM EDTFlash Flood WarningGSPBuncombe, Henderson, Polk, Rutherford8 hr
Aug 17, 4:50 PM EDTFlash Flood WarningGSPMcDowell9 hr
Aug 17, 4:58 PM EDTFlash Flood WarningGSPYancey4 hr
Aug 17, 4:59 PM EDTTornado WarningGSPAvery, Burke, McDowell, Mitchell, Yancey46 min
Aug 17, 5:14 PM EDTFlash Flood Warning Considerable damage threatGSPTransylvania4 hr
Aug 17, 5:17 PM EDTRiver Flood WarningGSPHaywood12 hr
Aug 17, 5:26 PM EDTTornado WarningGSPAvery, McDowell, Mitchell, Rutherford, Yancey49 min
Aug 17, 5:28 PM EDTTornado WarningGSPAvery, Burke, Caldwell47 min
Aug 17, 5:32 PM EDTFlash Flood WarningGSPMitchell4 hr
Aug 17, 5:48 PM EDTRiver Flood WarningGSPBuncombe26 hr
Aug 17, 6:16 PM EDTFlash Flood WarningGSPHenderson, Polk, Rutherford3 hr
Aug 17, 6:42 PM EDTTornado WarningGSPPolk, Rutherford48 min
Aug 17, 6:57 PM EDTFlash Flood WarningGSPBurke, McDowell6 hr
Aug 17, 7:59 PM EDTTornado WarningGSPCleveland46 min

Nearby

Flash 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.