Alert archive / North Carolina / Flash Flood Warnings in 2021

Flash Flood Warning 28, NWS Greenville-Spartanburg, SC

August 17, 2021McDowell County, North Carolina

NWS Greenville-Spartanburg, SC issued this flash flood warning at Aug 17, 2021, 4:50 PM EDT for McDowell County, North Carolina. It was in force for 9 hr. 4 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, 4:50 PM EDT (20:50 UTC)
Expired
Aug 18, 2021, 1:21 AM EDT
In force
9 hr
Issued by
NWS Greenville-Spartanburg, SC
Area
Storm-based polygon
Flood severity
None

County McDowell County, NC

The radar

The Greer radar (KGSP), 95 km from the middle of the area, began a volume at 20:49 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, 6:25 PM EDTFLASH FLOOD1 Wnw Old Fort, NCFLASH FLOODING UNDERWAY ON MILL CREEK NEAR SIMMONS ROAD
Aug 17, 7:39 PM EDTFLASH FLOOD5 Ssw Old Fort, NCFLASH FLOODING ALONG CROOKED CREEK NEAR MURPHYS DRIVE
Aug 17, 8:20 PM EDTFLASH FLOOD1 Ne Woodlawn, NCFLASH FLOODING ONSET NEAR AMERICAN THREAD ROAD
Aug 17, 8:37 PM EDTFLASH FLOOD2 N Woodlawn, NCFLASH FLOODING IN PROGRESS ON COX CREEK

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, 8.8 hours before the alert went out and 202 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.

565 
WGUS52 KGSP 172050
FFWGSP
NCC111-180045-
/O.NEW.KGSP.FF.W.0028.210817T2050Z-210818T0045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

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

The National Weather Service in Greenville-Spartanburg has issued a

* Flash Flood Warning for...
  Central McDowell County in western North Carolina...

* Until 845 PM EDT.

* At 450 PM EDT, As much as 5 or 6 inches of rain may accumulate by 
  this evening in the higher terrain above the Catawba River 
  headwaters in western McDowell County.  Remain wary of quickly 
  rising stream levels and the possibility of a few mud or 
  landslides.

  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...
  Marion, Old Fort, Lake James, B.R. Parkway-Little Switzerland To 
  Linville, Pleasant Gardens, Woodlawn, Little Switzerland, North 
  Cove and Ashford.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3588 8202 3587 8200 3589 8197 3589 8193
      3586 8193 3582 8199 3576 8199 3572 8196
      3567 8203 3562 8206 3554 8212 3553 8215
      3556 8223 3559 8229 3561 8226 3563 8225
      3569 8228 3569 8225 3573 8218 3584 8210

FLASH FLOOD...RADAR INDICATED

$$
2 follow-up statements
911 
WGUS52 KGSP 180043
FFWGSP
NCC111-180630-
/O.EXT.KGSP.FF.W.0028.000000T0000Z-210818T0630Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

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

The National Weather Service in Greenville-Spartanburg has extended 
the

* Flash Flood Warning for...
  Central McDowell County in western North Carolina...

* Until 230 AM EDT.

* At 843 PM EDT, McDowell County Emergency Management reporting 
  expanding flooding issues across the county. A few landslides have 
  been reported and several roads are closed.  Additional road 
  closures are expected.  Between 2 and 4 inches of rain have 
  fallen, but very little additional rainfall is expected.  However, 
  it will take several hours for excessive runoff to subside and for 
  area streams to crest and recede.  Therefore, please do not let 
  your guard down and avoid all low-lying areas adjacent to 
  streams.  Do NOT cross flooded roadways as those roadways may have 
  been damaged by swift currents.  Avoid all low-water crossings as 
  flood waters can rise quickly and without warning.

  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.  A few
           structures may experience flooding and a few roadways
           may be damaged or washed out from strong flood waters.
           A few landslides may also occur.

* Some locations that may experience increasing flash flooding 
  include...
  Marion, Old Fort, Lake James, Pleasant Gardens, Woodlawn, Little 
  Switzerland, North Cove and Ashford.

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 3588 8202 3587 8200 3589 8197 3589 8193
      3586 8193 3582 8199 3576 8199 3572 8196
      3567 8203 3562 8206 3554 8212 3553 8215
      3556 8223 3559 8229 3561 8226 3563 8225
      3569 8228 3569 8225 3573 8218 3584 8210

FLASH FLOOD...OBSERVED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE
EXPECTED RAINFALL...0.5 INCHES IN 2 HOURS

$$

JMP
898 
WGUS72 KGSP 180521
FFSGSP

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

NCC111-180531-
/O.CAN.KGSP.FF.W.0028.000000T0000Z-210818T0630Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
McDowell NC-
121 AM EDT Wed Aug 18 2021

...FLASH FLOOD WARNING IS CANCELLED FOR CENTRAL MCDOWELL COUNTY...

The heavy rain has ended across McDowell County and small streams 
across the area have crested and receded below critical levels. 
However, nuisance flooding continues for the Catawba River from 
Pleasant Gardens to Lake James.  Therefore, a Flood Advisory will 
remain in effect for the Catawba River until levels recede below 
bankfull.  Please continue to heed all barricades which remain in 
place to ensure roadway safety.

LAT...LON 3588 8202 3587 8200 3589 8197 3589 8193
      3586 8193 3582 8199 3576 8199 3572 8196
      3567 8203 3562 8206 3554 8212 3553 8215
      3556 8223 3559 8229 3561 8226 3563 8225
      3569 8228 3569 8225 3573 8218 3584 8210

$$

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, 4:58 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, 6:00 PM EDTFlash Flood WarningGSPAvery, Burke, Caldwell9 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.