Alert archive / Virginia / Flash Flood Warnings in 2021

Flash Flood Warning 14, NWS Blacksburg, VA

July 1, 2021Henry County, City of Martinsville, Virginia

NWS Blacksburg, VA issued this flash flood warning at Jul 1, 2021, 9:45 PM EDT for Henry County, City of Martinsville, Virginia. It was in force for 6 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: Jul 1, 2021, 9:45 PM EDT (01:45 UTC)
Expired: Jul 2, 2021, 3:45 AM EDT
In force: 6 hr
Issued by: NWS Blacksburg, VA
Area: Storm-based polygon
Flood severity: None

Counties City of Martinsville, VA, Henry County, VA

The radar

The Roanoke radar (KFCX), 50 km from the middle of the area, began a volume at 01:48 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
Jul 1, 10:00 PM EDT	FLOOD	1 E Villa Heights, VA	WATER REPORTED OVER ONE LANE OF COMMONWEALTH BOULEVARD.

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 00:00Z, 1.8 hours before the alert went out and 65 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: 65 J/kg
Mixed-layer CIN: -39 J/kg
Mixed-layer LCL: 702 m above ground
0-6 km bulk shear: 33 kt
0-1 km storm-relative helicity: 49 m²/s²
0-3 km storm-relative helicity: 60 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.1

Open this sounding in Storm Lab

The text

As transmitted.

653 
WGUS51 KRNK 020145
FFWRNK
VAC089-690-020745-
/O.NEW.KRNK.FF.W.0014.210702T0145Z-210702T0745Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Blacksburg VA
945 PM EDT Thu Jul 1 2021

The National Weather Service in Blacksburg has issued a

* Flash Flood Warning for...
  Central Henry County in south central Virginia...
  The City of Martinsville in south central Virginia...

* Until 345 AM EDT.

* At 945 PM EDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 1 and 2 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...
  Martinsville, Villa Heights, Collinsville, Fieldale and Chatmoss.

This includes the following streams and drainages...
  Hairston Branch, Smith River, Leatherwood Creek, Mulberry Creek, 
  Reed Creek and Beaver Creek.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Be especially cautious at night when it is harder to recognize the 
dangers of flooding.

&&

LAT...LON 3672 7995 3674 7992 3672 7984 3665 7980
      3664 7984

FLASH FLOOD...RADAR INDICATED

$$

AS

2 follow-up statements

289 
WGUS71 KRNK 020508
FFSRNK

Flash Flood Statement
National Weather Service Blacksburg VA
108 AM EDT Fri Jul 2 2021

VAC089-690-020745-
/O.CON.KRNK.FF.W.0014.000000T0000Z-210702T0745Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Henry VA-City of Martinsville VA-
108 AM EDT Fri Jul 2 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 345 AM EDT EARLY THIS 
MORNING FOR CENTRAL HENRY COUNTY AND THE CITY OF MARTINSVILLE...

At 108 AM EDT, Doppler radar indicated that the heavy rain producing 
showers and storms that prompted the warning have exited the area. 
The combination of runoff from this earlier heavy rain, and nearly 
continuous light rain currently falling across the area, may still 
lead to some locations with flash flooding.

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...
  Martinsville, Villa Heights, Collinsville, Fieldale and Chatmoss.

This includes the following streams and drainages...
  Hairston Branch, Smith River, Leatherwood Creek, Mulberry Creek, 
  Reed Creek and Beaver Creek.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Be especially cautious at night when it is harder to recognize the 
dangers of flooding.

&&

LAT...LON 3672 7995 3674 7992 3672 7984 3665 7980
      3664 7984

FLASH FLOOD...RADAR INDICATED

$$

DS

612 
WGUS71 KRNK 020754
FFSRNK

Flash Flood Statement
National Weather Service Blacksburg VA
354 AM EDT Fri Jul 2 2021

VAC089-690-020804-
/O.EXP.KRNK.FF.W.0014.000000T0000Z-210702T0745Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Henry VA-City of Martinsville VA-
354 AM EDT Fri Jul 2 2021

...FLASH FLOOD WARNING HAS EXPIRED FOR CENTRAL HENRY COUNTY AND THE 
CITY OF MARTINSVILLE...

While light to moderate rain remains across the warned area, 
rainfall rates and additional amounts of rain are not expected to 
prompt any additional flash flooding. Residual ponding of water from 
earlier heavy rains is still possible.

LAT...LON 3672 7995 3674 7992 3672 7984 3665 7980
      3664 7984

$$

DS

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 1, 8:01 PM EDT	Special Weather Statement	RNK	Pittsylvania, City of Martinsville	29 min
Jul 1, 8:34 PM EDT	Areal Flood Advisory	RNK	Grayson	3 hr
Jul 1, 8:52 PM EDT	Areal Flood Advisory	RNK	Franklin, Henry, Patrick, Pittsylvania, City of Martinsville	4 hr
Jul 1, 9:32 PM EDT	Special Weather Statement	RNK	City of Martinsville	28 min
Jul 1, 9:58 PM EDT	Special Weather Statement	RNK	Pittsylvania, City of Danville	32 min
Jul 1, 10:24 PM EDT	Severe Thunderstorm Warning	RNK	Charlotte, Halifax	66 min
Jul 1, 11:41 PM EDT	Special Weather Statement	RNK	Halifax	34 min
Jul 2, 12:04 AM EDT	Special Weather Statement	RNK	Halifax	26 min

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.