Alert archive / Virginia / Flash Flood Warnings in 2021

Flash Flood Warning 53, NWS Wakefield, VA

August 20, 20216 counties in Virginia

NWS Wakefield, VA issued this flash flood warning at Aug 20, 2021, 3:40 AM EDT for 6 counties in Virginia. It was in force for 3 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 20, 2021, 3:40 AM EDT (07:40 UTC)
Expired: Aug 20, 2021, 6:45 AM EDT
In force: 3 hr
Issued by: NWS Wakefield, VA
Area: Storm-based polygon
Flood severity: None

Counties Charles City County, VA, Chesterfield County, VA, City of Colonial Heights, VA, City of Hopewell, VA, City of Petersburg, VA, Prince George County, VA

The radar

The Norfolk radar (KAKQ), 44 km from the middle of the area, began a volume at 07:43 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
Aug 20, 3:40 AM EDT	FLASH FLOOD	Hopewell, VA	PORTIONS OF RANDOLPH RD CLOSED DUE TO HIGH WATER.

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

The nearest sounding before it

Wallops Is Stn, VA (KWAL), launched 00:00Z, 7.7 hours before the alert went out and 181 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: 1543 J/kg
Mixed-layer CIN: -19 J/kg
Mixed-layer LCL: 1030 m above ground
0-6 km bulk shear: 14 kt
0-1 km storm-relative helicity: 6 m²/s²
0-3 km storm-relative helicity: 14 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.3

Open this sounding in Storm Lab

The text

As transmitted.

997 
WGUS51 KAKQ 200740
FFWAKQ
VAC036-041-149-570-670-730-201045-
/O.NEW.KAKQ.FF.W.0053.210820T0740Z-210820T1045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Wakefield VA
340 AM EDT Fri Aug 20 2021

The National Weather Service in Wakefield has issued a

* Flash Flood Warning for...
  Southeastern Chesterfield County in central Virginia...
  The City of Colonial Heights in central Virginia...
  West Central Charles City County in east central Virginia...
  Northwestern Prince George County in south central Virginia...
  The City of Hopewell in south central Virginia...
  The Northeastern City of Petersburg in south central Virginia...

* Until 645 AM EDT.

* At 340 AM EDT, Doppler radar and automated rain gauges indicated 
  thunderstorms producing heavy rain across the warned area. Between 
  1.5 and 2.5 inches of rain have fallen. Additional rainfall 
  amounts of 0.5 to 1 inch are possible in the warned area. 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...
  Petersburg, Hopewell, Colonial Heights, Fort Lee, Chester, Prince 
  George, Jordans Point, Ettrick, Birchett Estate, Jordan Point 
  Country Club and Petersburg National Battlefield.

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. Do not stay in areas subject to flooding when 
water begins rising.

&&

LAT...LON 3733 7741 3736 7730 3735 7729 3735 7728
      3735 7727 3736 7727 3735 7721 3727 7721
      3722 7721 3721 7729 3721 7742

FLASH FLOOD...RADAR AND GAUGE INDICATED

$$

RMM

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 19, 11:56 PM EDT	Special Weather Statement	AKQ	Nottoway	64 min
Aug 20, 12:43 AM EDT	Areal Flood Advisory	AKQ	Lunenburg, Nottoway, Prince Edward	3 hr
Aug 20, 12:50 AM EDT	Special Weather Statement	AKQ	Brunswick	55 min
Aug 20, 1:48 AM EDT	Areal Flood Advisory	AKQ	Chesterfield, Goochland, Henrico, Powhatan, City of Richmond	117 min
Aug 20, 2:07 AM EDT	Special Weather Statement	AKQ	Dinwiddie, City of Colonial Heights, City of Petersburg	53 min
Aug 20, 2:09 AM EDT	Special Weather Statement	AKQ	Amelia, Lunenburg, Nottoway	66 min
Aug 20, 2:15 AM EDT	Special Weather Statement	AKQ	Essex, King William, Richmond	60 min
Aug 20, 2:46 AM EDT	Special Weather Statement	AKQ	Charles City, Henrico, James City, King and Queen, New Kent, Prince George and 4 more	59 min
Aug 20, 2:59 AM EDT	Small Craft Advisory	AKQ		51 hr
Aug 20, 3:11 AM EDT	Areal Flood Advisory	AKQ	Charles City, Chesterfield, Henrico, Prince George, City of Colonial Heights, City of Hopewell and 1 more	3 hr
Aug 20, 4:00 AM EDT	Special Weather Statement	AKQ	Essex, Gloucester, James City, King and Queen, King William, Lancaster and 6 more	60 min
Aug 20, 4:15 AM EDT	River Flood Warning	AKQ	Charles City, New Kent	3 days
Aug 20, 4:41 AM EDT	Special Marine Warning	AKQ		94 min
Aug 20, 5:18 AM EDT	Special Weather Statement	AKQ	Accomack	57 min
Aug 20, 6:05 AM EDT	Special Marine Warning	AKQ		85 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.