Alert archive / West Virginia / Flash Flood Warnings in 2021

Flash Flood Warning 24, NWS Baltimore/Washington

July 12, 2021Berkeley County, Jefferson County, West Virginia

NWS Baltimore/Washington issued this flash flood warning at Jul 12, 2021, 3:30 PM EDT for Berkeley County, Jefferson County, West Virginia. It was in force for 2 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 12, 2021, 3:30 PM EDT (19:30 UTC)
Expired
Jul 12, 2021, 5:48 PM EDT
In force
2 hr
Issued by
NWS Baltimore/Washington
Area
Storm-based polygon
Flood severity
None

Counties Berkeley County, WV, Jefferson County, WV

The radar

The Sterling radar (KLWX), 57 km from the middle of the area, began a volume at 19:30 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

Washington/Dulle, VA (KIAD), launched 12:00Z, 7.5 hours before the alert went out and 64 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 2021-07-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 974 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 2021-07-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 10 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
974 J/kg
Mixed-layer CIN
-83 J/kg
Mixed-layer LCL
724 m above ground
0-6 km bulk shear
21 kt
0-1 km storm-relative helicity
10 m²/s²
0-3 km storm-relative helicity
53 m²/s²
Significant tornado parameter
0.1
Supercell composite
0.8

Open this sounding in Storm Lab

The text

As transmitted.

839 
WGUS51 KLWX 121930
FFWLWX
WVC003-037-122230-
/O.NEW.KLWX.FF.W.0024.210712T1930Z-210712T2230Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Baltimore MD/Washington DC
330 PM EDT Mon Jul 12 2021

The National Weather Service in Sterling Virginia has issued a

* Flash Flood Warning for...
  Southeastern Berkeley County in the panhandle of West Virginia...
  Central Jefferson County in the panhandle of West Virginia...

* Until 630 PM EDT.

* At 330 PM EDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 1 and 2 inches of rain 
  have fallen. Additional rainfall amounts of 1 to 2 inches are 
  possible in the warned area. 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...
  Shepherdstown...                   Ranson...
  Kearneysville...                   Shenandoah Junction...
  Middleway...                       Winebrenners Cross...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3930 7806 3947 7786 3948 7783 3944 7780
      3943 7780 3943 7779 3941 7777 3924 7798

FLASH FLOOD...RADAR INDICATED

$$

RCM
2 follow-up statements
290 
WGUS71 KLWX 122041
FFSLWX

Flash Flood Statement
National Weather Service Baltimore MD/Washington DC
441 PM EDT Mon Jul 12 2021

WVC003-122051-
/O.CAN.KLWX.FF.W.0024.000000T0000Z-210712T2230Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Berkeley WV-
441 PM EDT Mon Jul 12 2021

...FLASH FLOOD WARNING IS CANCELLED FOR SOUTHEASTERN BERKELEY 
COUNTY...

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

LAT...LON 3932 7799 3939 7791 3942 7787 3943 7784
      3942 7781 3941 7781 3939 7782 3934 7787
      3929 7792 3926 7799 3928 7803 3929 7803
      3929 7802 3931 7801

$$

WVC037-122230-
/O.CON.KLWX.FF.W.0024.000000T0000Z-210712T2230Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Jefferson WV-
441 PM EDT Mon Jul 12 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 630 PM EDT THIS 
EVENING FOR CENTRAL JEFFERSON COUNTY...

At 441 PM EDT, Doppler radar indicated thunderstorms producing heavy 
rain across the warned area. Between 3 and 4 inches of rain have 
fallen. Additional rainfall amounts of 0.5 to 1.5 inches are 
possible in the warned area. Flash flooding is ongoing or expected 
to begin shortly.

Areas between Charles Town and Middleway along Middleway Pike and 
Darke Lane near Browns Corner are the most likely places to 
experience 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...
  Ranson...                          Kearneysville...
Middleway...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3932 7799 3939 7791 3942 7787 3943 7784
      3942 7781 3941 7781 3939 7782 3934 7787
      3929 7792 3926 7799 3928 7803 3929 7803
      3929 7802 3931 7801

FLASH FLOOD...RADAR INDICATED

$$

LEE
251 
WGUS71 KLWX 122148
FFSLWX

Flash Flood Statement
National Weather Service Baltimore MD/Washington DC
548 PM EDT Mon Jul 12 2021

WVC037-122158-
/O.CAN.KLWX.FF.W.0024.000000T0000Z-210712T2230Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Jefferson WV-
548 PM EDT Mon Jul 12 2021

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

Flood waters have receded. The heavy rain has ended. Flooding is no 
longer expected to pose a threat. Please continue to heed remaining 
road closures.

LAT...LON 3932 7799 3939 7791 3942 7787 3943 7784
      3942 7781 3941 7781 3939 7782 3934 7787
      3929 7792 3926 7799 3928 7803 3929 7803
      3929 7802 3931 7801

$$

RCM

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 11, 8:28 PM EDTSevere Thunderstorm WarningLWXBerkeley, Hampshire, Morgan47 min
Jul 12, 2:43 PM EDTSevere Thunderstorm WarningLWXBerkeley, Jefferson47 min
Jul 12, 3:15 PM EDTSevere Thunderstorm WarningLWXJefferson22 min
Jul 12, 3:43 PM EDTSevere Thunderstorm WarningLWXBerkeley, Jefferson47 min
Jul 12, 4:36 PM EDTSevere Thunderstorm WarningLWXBerkeley, Hampshire, Morgan39 min
Jul 12, 4:59 PM EDTSevere Thunderstorm WarningLWXBerkeley, Jefferson29 min

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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.