Alert archive / North Carolina / Flash Flood Warnings in 2021

Flash Flood Warning 20, NWS Blacksburg, VA

July 17, 2021Caswell County, Rockingham County, North Carolina; Pittsylvania County, City of Danville, Virginia

NWS Blacksburg, VA issued this flash flood warning at Jul 17, 2021, 4:11 PM EDT for Caswell County, Rockingham County, North Carolina; Pittsylvania County, City of Danville, Virginia. It was in force for 3 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
Jul 17, 2021, 4:11 PM EDT (20:11 UTC)
Expired
Jul 17, 2021, 7:15 PM EDT
In force
3 hr
Issued by
NWS Blacksburg, VA
Area
Storm-based polygon
Flood severity
None

Counties Caswell County, NC, Rockingham County, NC, City of Danville, VA, Pittsylvania County, VA

The radar

The Roanoke radar (KFCX), 92 km from the middle of the area, began a volume at 20:13 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

Greensboro/Hi Pt, NC (KGSO), launched 12:00Z, 8.2 hours before the alert went out and 63 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 2021-07-17Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 966 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 2021-07-17The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 12 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
966 J/kg
Mixed-layer CIN
-78 J/kg
Mixed-layer LCL
843 m above ground
0-6 km bulk shear
13 kt
0-1 km storm-relative helicity
12 m²/s²
0-3 km storm-relative helicity
19 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

652 
WGUS51 KRNK 172011
FFWRNK
NCC033-157-VAC143-590-172315-
/O.NEW.KRNK.FF.W.0020.210717T2011Z-210717T2315Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Blacksburg VA
411 PM EDT Sat Jul 17 2021

The National Weather Service in Blacksburg has issued a

* Flash Flood Warning for...
  Western Caswell County in north central North Carolina...
  Eastern Rockingham County in north central North Carolina...
  South Central Pittsylvania County in south central Virginia...
  The City of Danville in south central Virginia...

* Until 715 PM EDT.

* At 411 PM EDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 1 and 3 inches of rain 
  have fallen. Flash flooding is ongoing or expected to begin 
  shortly.

  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...
  Danville, Reidsville, Yanceyville, Bethel, Providence, Mayfield 
  and Camp Springs.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3661 7951 3664 7940 3665 7938 3660 7926
      3626 7945 3627 7968

FLASH FLOOD...RADAR INDICATED

$$

RR
2 follow-up statements
425 
WGUS71 KRNK 172114
FFSRNK

Flash Flood Statement
National Weather Service Blacksburg VA
514 PM EDT Sat Jul 17 2021

VAC143-590-172124-
/O.CAN.KRNK.FF.W.0020.000000T0000Z-210717T2315Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Pittsylvania VA-City of Danville VA-
514 PM EDT Sat Jul 17 2021

...FLASH FLOOD WARNING IS CANCELLED FOR SOUTH CENTRAL PITTSYLVANIA 
COUNTY AND THE CITY OF DANVILLE...

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

LAT...LON 3654 7954 3654 7951 3654 7948 3654 7947
      3654 7945 3654 7943 3654 7938 3654 7934
      3654 7933 3654 7930 3626 7945 3627 7968

$$

NCC033-157-172315-
/O.CON.KRNK.FF.W.0020.000000T0000Z-210717T2315Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Caswell NC-Rockingham NC-
514 PM EDT Sat Jul 17 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 715 PM EDT THIS 
EVENING FOR WESTERN CASWELL AND EASTERN ROCKINGHAM COUNTIES...

At 514 PM EDT, Doppler radar indicated thunderstorms producing heavy 
rain across the warned area. Between 1 and 5 inches of rain have 
fallen. Flash flooding is ongoing or expected to begin shortly.

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...
  Reidsville, Yanceyville, Bethel, Camp Springs, Providence, Quick 
  and Ruffin.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3654 7954 3654 7951 3654 7948 3654 7947
      3654 7945 3654 7943 3654 7938 3654 7934
      3654 7933 3654 7930 3626 7945 3627 7968

FLASH FLOOD...RADAR INDICATED

$$

RR
376 
WGUS71 KRNK 172308
FFSRNK

Flash Flood Statement
National Weather Service Blacksburg VA
708 PM EDT Sat Jul 17 2021

NCC033-157-172318-
/O.EXP.KRNK.FF.W.0020.000000T0000Z-210717T2315Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Caswell NC-Rockingham NC-
708 PM EDT Sat Jul 17 2021

...FLASH FLOOD WARNING WILL EXPIRE AT 715 PM EDT THIS EVENING FOR 
WESTERN CASWELL AND EASTERN ROCKINGHAM COUNTIES...

Flood waters are receding. The heavy rain has ended. Flooding is no 
longer expected to pose an immediate threat. Please continue to heed 
remaining road closures. A flood advisory remains in effect for this 
area.

LAT...LON 3654 7954 3654 7951 3654 7948 3654 7947
      3654 7945 3654 7943 3654 7938 3654 7934
      3654 7933 3654 7930 3626 7945 3627 7968

$$

RR

The office that day

Everything else NWS Blacksburg, VA issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 17, 1:06 PM EDTSpecial Weather StatementRNKSurry39 min
Jul 17, 1:45 PM EDTSevere Thunderstorm WarningRNKSurry43 min
Jul 17, 2:11 PM EDTAreal Flood AdvisoryRNKSurry3 hr
Jul 17, 2:49 PM EDTSpecial Weather StatementRNKCaswell26 min
Jul 17, 2:56 PM EDTSevere Thunderstorm WarningRNKCaswell, Rockingham49 min
Jul 17, 3:42 PM EDTSpecial Weather StatementRNKCaswell, Rockingham48 min
Jul 17, 3:48 PM EDTSevere Thunderstorm WarningRNKCaswell, Rockingham57 min
Jul 17, 3:52 PM EDTAreal Flood AdvisoryRNKCaswell, Rockingham3 hr
Jul 17, 4:00 PM EDTSevere Thunderstorm WarningRNKCaswell, Rockingham60 min
Jul 17, 5:00 PM EDTSevere Thunderstorm WarningRNKCaswell, Rockingham60 min
Jul 17, 5:10 PM EDTSpecial Weather StatementRNKWilkes35 min
Jul 17, 5:39 PM EDTSpecial Weather StatementRNKWilkes36 min
Jul 17, 6:02 PM EDTSpecial Weather StatementRNKCaswell13 min
Jul 17, 6:08 PM EDTSpecial Weather StatementRNKAlleghany, Surry, Watauga, Wilkes67 min
Jul 17, 6:50 PM EDTAreal Flood AdvisoryRNKCaswell, Rockingham7 hr
Jul 17, 7:05 PM EDTSpecial Weather StatementRNKAlleghany, Surry40 min
Jul 17, 7:10 PM EDTAreal Flood AdvisoryRNKAlleghany, Surry3 hr
Jul 17, 7:34 PM EDTSpecial Weather StatementRNKYadkin26 min
Jul 17, 7:44 PM EDTSevere Thunderstorm WarningRNKAlleghany, Rockingham, Stokes, Surry, Wilkes, Yadkin61 min
Jul 16, 8:21 PM EDTSpecial Weather StatementRNKWythe24 min
Jul 17, 12:01 PM EDTSpecial Weather StatementRNKBedford, Franklin29 min
Jul 17, 12:26 PM EDTSevere Thunderstorm WarningRNKFranklin49 min
Jul 17, 12:47 PM EDTSpecial Weather StatementRNKBedford28 min
Jul 17, 1:20 PM EDTSpecial Weather StatementRNKFranklin25 min
Jul 17, 1:33 PM EDTSpecial Weather StatementRNKBedford42 min
Jul 17, 1:38 PM EDTSpecial Weather StatementRNKCarroll37 min
Jul 17, 1:43 PM EDTSpecial Weather StatementRNKCampbell47 min
Jul 17, 1:56 PM EDTSevere Thunderstorm WarningRNKAmherst, Appomattox, Campbell, City of Lynchburg64 min
Jul 17, 2:14 PM EDTAreal Flood AdvisoryRNKAppomattox, Campbell3 hr
Jul 17, 2:37 PM EDTSevere Thunderstorm WarningRNKAppomattox, Campbell, Charlotte53 min
Jul 17, 2:45 PM EDTSpecial Weather StatementRNKPatrick30 min
Jul 17, 2:47 PM EDTSpecial Weather StatementRNKCity of Martinsville28 min
Jul 17, 2:53 PM EDTSevere Thunderstorm WarningRNKFranklin, Henry, Pittsylvania, City of Martinsville36 min
Jul 17, 2:59 PM EDTSpecial Weather StatementRNKFranklin31 min
Jul 17, 3:00 PM EDTSpecial Weather StatementRNKPrince Edward15 min
Jul 17, 3:16 PM EDTAreal Flood AdvisoryRNKFranklin2 hr
Jul 17, 3:24 PM EDTSpecial Weather StatementRNKFranklin36 min
Jul 17, 3:27 PM EDTSpecial Weather StatementRNKTazewell48 min
Jul 17, 3:54 PM EDTSpecial Weather StatementRNKHalifax36 min
Jul 17, 4:17 PM EDTSpecial Weather StatementRNKBland, Giles, Smyth, Tazewell43 min
Jul 17, 4:22 PM EDTSpecial Weather StatementRNKCharlotte23 min
Jul 17, 4:26 PM EDTSpecial Weather StatementRNKHalifax34 min
Jul 17, 4:47 PM EDTSpecial Weather StatementRNKCharlotte28 min
Jul 17, 5:01 PM EDTSpecial Weather StatementRNKAlleghany, Bath, Craig, Giles, City of Covington59 min
Jul 17, 5:26 PM EDTSpecial Weather StatementRNKAppomattox34 min
Jul 17, 5:45 PM EDTSpecial Weather StatementRNKFloyd30 min
Jul 17, 6:04 PM EDTSpecial Weather StatementRNKAmherst, Botetourt, Montgomery, Roanoke, Rockbridge, City of Buena Vista and 3 more56 min
Jul 17, 6:19 PM EDTSpecial Weather StatementRNKFloyd26 min
Jul 17, 6:25 PM EDTSevere Thunderstorm WarningRNKAmherst, Bedford, Botetourt, Rockbridge, City of Buena Vista, City of Lexington65 min
Jul 17, 6:58 PM EDTSpecial Weather StatementRNKCity of Roanoke, City of Salem47 min
Jul 17, 7:30 PM EDTSevere Thunderstorm WarningRNKBedford, Campbell, City of Lynchburg39 min

Nearby

Flash Flood Warnings in North Carolina, 2021Flash Flood Warnings in Virginia, 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.