Alert archive / Virginia / Flash Flood Warnings in 2021

Flash Flood Warning 42, NWS Blacksburg, VA

September 22, 20215 counties in Virginia

NWS Blacksburg, VA issued this flash flood warning at Sep 22, 2021, 5:32 PM EDT for 5 counties in Virginia. It was in force for 3 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: Sep 22, 2021, 5:32 PM EDT (21:32 UTC)
Expired: Sep 22, 2021, 8:30 PM EDT
In force: 3 hr
Issued by: NWS Blacksburg, VA
Area: Storm-based polygon
Flood severity: None

Counties Bedford County, VA, Botetourt County, VA, City of Buena Vista, VA, City of Lexington, VA, Rockbridge County, VA

The radar

The Roanoke radar (KFCX), 100 km from the middle of the area, began a volume at 21:33 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

Time	Report	Where	Remark
Sep 22, 5:56 PM EDT	FLOOD	2 Nw Lexington, VA	ROUTE 60 FLOODED IN LEXINGTON.
Sep 22, 6:45 PM EDT	FLASH FLOOD	1 Nnw Arcadia, VA	RENICK RUN FLOODED INDIAN ROCK ROAD, CAUSING THE ROAD TO CRUMBLE AND BECOME IMPASSABLE.
Sep 22, 7:10 PM EDT	FLASH FLOOD	1 Nnw Arcadia, VA	BRIDGE OVER RENICK RUN WASHED OUT ON INDIAN ROCK ROAD.
Sep 22, 7:41 PM EDT	FLASH FLOOD	5 Ese Buchanan, VA	OCCUPANTS ESCAPED FROM RISING WATER BUT VEHICLE WAS WASHED AWAY WHEN JENNINGS CREEK FLOODED JENNINGS CREEK ROAD.

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

The nearest sounding before it

Roanoke, VA (KRNK), launched 12:00Z, 9.5 hours before the alert went out and 50 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 266 J/kg
Mixed-layer CIN: -2 J/kg
Mixed-layer LCL: 555 m above ground
0-6 km bulk shear: 24 kt
0-1 km storm-relative helicity: 97 m²/s²
0-3 km storm-relative helicity: 119 m²/s²
Significant tornado parameter: 0.1
Supercell composite: 0.6

Open this sounding in Storm Lab

The text

As transmitted.

925 
WGUS51 KRNK 222132
FFWRNK
VAC019-023-163-530-678-230030-
/O.NEW.KRNK.FF.W.0042.210922T2132Z-210923T0030Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Blacksburg VA
532 PM EDT Wed Sep 22 2021

The National Weather Service in Blacksburg has issued a

* Flash Flood Warning for...
  Northwestern Bedford County in south central Virginia...
  East Central Botetourt County in west central Virginia...
  Southern Rockbridge County in west central Virginia...
  The City of Buena Vista in west central Virginia...
  The City of Lexington in west central Virginia...

* Until 830 PM EDT.

* At 532 PM EDT, Doppler radar and automated rain gauges indicated 
  thunderstorms producing heavy rain across the warned area. Up to 4 
  inches of rain have fallen over portions of the area this 
  afternoon. The expected rainfall rate is 4 inches in 1 hour. 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.

* Some locations that will experience flash flooding include...
  Lexington...                       Buena Vista...
  Buchanan...                        Glasgow...
  Natural Bridge...                  Arcadia...
  Peaks Of Otter Summit...

This includes the following locations...
	VMI.

This includes the following streams and drainages...
  Buffalo Creek, Cold Run, Broad Creek, Big Hollow Branch, Cornelius 
  Creek, Back Run, Big Otter River, Davidson Run, Alone Mill Creek 
  and Dry Branch.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Be aware of your surroundings and do not drive on flooded roads.

&&

LAT...LON 3789 7947 3782 7923 3763 7940 3761 7944
      3760 7944 3761 7942 3739 7959 3742 7973

FLASH FLOOD...RADAR AND GAUGE INDICATED
EXPECTED RAINFALL...4 INCHES IN 1 HOUR

$$

WP

2 follow-up statements

027 
WGUS71 KRNK 222253
FFSRNK

Flash Flood Statement
National Weather Service Blacksburg VA
653 PM EDT Wed Sep 22 2021

VAC019-023-163-530-678-230030-
/O.CON.KRNK.FF.W.0042.000000T0000Z-210923T0030Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Bedford VA-Botetourt VA-Rockbridge VA-City of Buena Vista VA-City of
Lexington VA-
653 PM EDT Wed Sep 22 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 830 PM EDT THIS 
EVENING FOR NORTHWESTERN BEDFORD, EAST CENTRAL BOTETOURT AND 
SOUTHERN ROCKBRIDGE COUNTIES AND THE CITY OF BUENA VISTA AND THE 
CITY OF LEXINGTON...

At 653 PM EDT, Doppler radar and automated rain gauges indicated 
thunderstorms producing heavy rain across the warned area. Up to 4 
inches of rain have fallen. 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.

Some locations that will experience flash flooding include...
  Lexington...                       Buena Vista...
Buchanan...                        Glasgow...
Natural Bridge...                  Arcadia...
Peaks Of Otter Summit...

This includes the following locations...
	VMI.

This includes the following streams and drainages...
  Buffalo Creek, Cold Run, Broad Creek, Big Hollow Branch, Cornelius 
  Creek, Back Run, Big Otter River, Davidson Run, Alone Mill Creek 
  and Dry Branch.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Be aware of your surroundings and do not drive on flooded roads.

&&

LAT...LON 3789 7947 3782 7923 3763 7940 3761 7944
      3760 7944 3761 7942 3739 7959 3742 7973

FLASH FLOOD...RADAR AND GAUGE INDICATED

$$

BMG

505 
WGUS71 KRNK 230023
FFSRNK

Flash Flood Statement
National Weather Service Blacksburg VA
823 PM EDT Wed Sep 22 2021

VAC019-023-163-530-678-230033-
/O.EXP.KRNK.FF.W.0042.000000T0000Z-210923T0030Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Bedford VA-Botetourt VA-Rockbridge VA-City of Buena Vista VA-City of
Lexington VA-
823 PM EDT Wed Sep 22 2021

...FLASH FLOOD WARNING WILL EXPIRE AT 830 PM EDT THIS EVENING FOR 
NORTHWESTERN BEDFORD, EAST CENTRAL BOTETOURT AND SOUTHERN ROCKBRIDGE 
COUNTIES AND THE CITY OF BUENA VISTA AND THE CITY OF LEXINGTON...

Flash 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 AM EDT Thursday for 
portions of north central North Carolina and Virginia.

LAT...LON 3789 7947 3782 7923 3763 7940 3761 7944
      3760 7944 3761 7942 3739 7959 3742 7973

$$

BMG

The office that day

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

Issued	Product	Office	Counties	Lasted
Sep 21, 8:07 PM EDT	Areal Flood Advisory	RNK	Floyd, Franklin	3 hr
Sep 21, 9:00 PM EDT	Areal Flood Advisory	RNK	Floyd, Franklin, Montgomery, Roanoke, City of Roanoke, City of Salem	3 hr
Sep 21, 9:34 PM EDT	Areal Flood Advisory	RNK	Carroll, Floyd, Patrick	3 hr
Sep 21, 10:10 PM EDT	Flash Flood Warning	RNK	Carroll, Floyd, Patrick	6 hr
Sep 21, 10:19 PM EDT	Areal Flood Advisory	RNK	Floyd, Patrick	3 hr
Sep 21, 11:25 PM EDT	Areal Flood Advisory	RNK	Floyd, Franklin	3 hr
Sep 21, 11:56 PM EDT	Areal Flood Advisory	RNK	Carroll, Floyd, Montgomery, Pulaski, City of Radford	6 hr
Sep 22, 12:20 AM EDT	Flash Flood Warning	RNK	Floyd, Patrick	4 hr
Sep 22, 1:00 AM EDT	Flash Flood Warning	RNK	Franklin, Roanoke, City of Roanoke, City of Salem	3 hr
Sep 22, 1:12 AM EDT	Flash Flood Warning	RNK	Montgomery	6 hr
Sep 22, 2:27 AM EDT	Flash Flood Warning	RNK	Craig, Giles	6 hr
Sep 22, 5:03 AM EDT	Areal Flood Advisory	RNK	Floyd, Franklin, Henry, Patrick	3 hr
Sep 22, 11:00 AM EDT	Areal Flood Advisory	RNK	Bedford, Botetourt, Floyd, Franklin, Henry, Patrick and 7 more	11 hr
Sep 22, 1:35 PM EDT	Special Weather Statement	RNK	City of Martinsville	25 min
Sep 22, 2:02 PM EDT	Special Weather Statement	RNK	Amherst	28 min
Sep 22, 2:52 PM EDT	Areal Flood Advisory	RNK	Craig, Giles, Montgomery, Pulaski, City of Radford	2 hr
Sep 22, 3:38 PM EDT	Special Weather Statement	RNK	Floyd, Montgomery	22 min
Sep 22, 4:01 PM EDT	Special Weather Statement	RNK	Patrick	29 min
Sep 22, 4:20 PM EDT	Special Weather Statement	RNK	Patrick	40 min
Sep 22, 4:27 PM EDT	Severe Thunderstorm Warning	RNK	Patrick	33 min
Sep 22, 4:35 PM EDT	Special Weather Statement	RNK	Franklin	40 min
Sep 22, 4:47 PM EDT	Special Weather Statement	RNK	Rockbridge, City of Buena Vista, City of Lexington	28 min
Sep 22, 4:53 PM EDT	Flash Flood Warning	RNK	Bedford, Franklin, Patrick, Roanoke	4 hr
Sep 22, 7:10 PM EDT	Areal Flood Warning	RNK	Rockbridge	2 hr
Sep 22, 7:19 PM EDT	Areal Flood Advisory	RNK	Amherst	3 hr

Nearby

Flash Flood Warnings in Virginia, 2021 Every 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.