Alert archive / West Virginia / Flash Flood Warnings in 2021

Flash Flood Warning 57, NWS Baltimore/Washington

August 28, 2021Grant County, West Virginia

NWS Baltimore/Washington issued this flash flood warning at Aug 28, 2021, 6:32 PM EDT for Grant County, West Virginia. It was in force for 3 hr. 2 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 28, 2021, 6:32 PM EDT (22:32 UTC)
Expired
Aug 28, 2021, 9:23 PM EDT
In force
3 hr
Issued by
NWS Baltimore/Washington
Area
Storm-based polygon
Damage threat
Considerable
Flood severity
None

County Grant County, WV

The radar

The Sterling radar (KLWX), 150 km from the middle of the area, began a volume at 22:33 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

TimeReportWhereRemark
Aug 28, 6:58 PM EDTFLASH FLOOD5 Wsw Cabins, WVMULTIPLE ROADS CLOSED DUE TO HIGH WATER FLOWING ACROSS THE ROAD. SEVERAL STREAMS ARE OVERFLOWING THEIR BANKS IN THE SOUTHWEST PORTION OF GRANT COUNTY.
Aug 28, 7:59 PM EDTFLOODMaysville, WVROUTE 42 IN MAYSVILLE 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

Washington/Dulle, VA (KIAD), launched 12:00Z, 10.5 hours before the alert went out and 158 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, Washington/Dulle, VA at 12:00Z on 2021-08-28Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 425 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, Washington/Dulle, VA at 12:00Z on 2021-08-28The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -11 square meters per square second.1939Sfc1 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
425 J/kg
Mixed-layer CIN
-107 J/kg
Mixed-layer LCL
898 m above ground
0-6 km bulk shear
9 kt
0-1 km storm-relative helicity
-11 m²/s²
0-3 km storm-relative helicity
11 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

317 
WGUS51 KLWX 282232
FFWLWX
WVC023-290145-
/O.NEW.KLWX.FF.W.0057.210828T2232Z-210829T0145Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Baltimore MD/Washington DC
632 PM EDT Sat Aug 28 2021

The National Weather Service in Sterling Virginia has issued a

* Flash Flood Warning for...
  Central Grant County in eastern West Virginia...

* Until 945 PM EDT.

* At 632 PM EDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 2 and 3 inches of rain 
  have fallen. Additional rainfall amounts of 1 to 3 inches are 
  possible in the warned area. Flash flooding is ongoing or expected 
  to begin shortly.

  HAZARD...Life threatening flash flooding. Thunderstorms
           producing flash flooding.

  SOURCE...Radar.

  IMPACT...Life threatening flash flooding of creeks and streams,
           urban areas, highways, streets and underpasses.

* Some locations that will experience flash flooding include...
  Streby...                          Kline Gap...
  Maysville...                       Hopeville...

This includes the following streams and drainages...
  Patterson Creek, Little Star Run, North Fork South Branch Potomac 
  River, South Branch Potomac River, Broad Run, Jordan Run, Norman 
  Run, Big Run, Redman Run, Saltblock Run, Moyer Run, Lunice Creek, 
  Robinson Run, South Fork Lunice Creek, Big Star Run, Laurel Run, 
  Middle Fork Patterson Creek and North Fork Patterson Creek.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3919 7919 3916 7911 3892 7927 3895 7934

FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE

$$

RCM
1 follow-up statement
264 
WGUS71 KLWX 290123
FFSLWX

Flash Flood Statement
National Weather Service Baltimore MD/Washington DC
923 PM EDT Sat Aug 28 2021

WVC023-290133-
/O.CAN.KLWX.FF.W.0057.000000T0000Z-210829T0145Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Grant WV-
923 PM EDT Sat Aug 28 2021

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

Flood waters are receding. The heavy rain has ended. Additional 
flooding is no longer expected to pose a threat. Please continue to 
heed remaining road closures. A flood warning remains in effect for 
existing high water which has yet to subside.

LAT...LON 3919 7919 3916 7911 3892 7927 3895 7934

$$

RCM

The office that day

Everything else NWS Baltimore/Washington issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 28, 4:46 PM EDTSevere Thunderstorm WarningLWXBerkeley, Hampshire, Morgan25 min
Aug 28, 4:56 PM EDTSevere Thunderstorm WarningLWXBerkeley, Jefferson49 min
Aug 28, 5:04 PM EDTSevere Thunderstorm WarningLWXBerkeley, Jefferson41 min
Aug 28, 5:27 PM EDTAreal Flood WarningLWXBerkeley, Jefferson3 hr
Aug 28, 6:15 PM EDTAreal Flood WarningLWXGrant3 hr
Aug 28, 6:51 PM EDTAreal Flood WarningLWXHardy3 hr
Aug 28, 7:20 PM EDTAreal Flood WarningLWXGrant, Hardy3 hr

Nearby

Flash Flood Warnings in West 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.