Alert archive / West Virginia / Flash Flood Warnings in 2021

Flash Flood Warning 26, NWS Blacksburg, VA

August 4, 2021Mercer County, Summers County, West Virginia

NWS Blacksburg, VA issued this flash flood warning at Aug 4, 2021, 10:39 PM EDT for Mercer County, Summers County, West Virginia. It was in force for 4 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 4, 2021, 10:39 PM EDT (02:39 UTC)
Expired
Aug 5, 2021, 2:13 AM EDT
In force
4 hr
Issued by
NWS Blacksburg, VA
Area
Storm-based polygon
Flood severity
None

Counties Mercer County, WV, Summers County, WV

The radar

The Roanoke radar (KFCX), 97 km from the middle of the area, began a volume at 02:40 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 4, 11:00 PM EDTHEAVY RAIN 54 S Odd, WV5.00 INCHES OF RAIN REPORTED AT EGERIA IFLOWS BETWEEN 9 PM AND 11 PM

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, 2.7 hours before the alert went out and 152 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, Roanoke, VA at 00:00Z on 2021-08-05Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 20 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, Roanoke, VA at 00:00Z on 2021-08-05The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -14 square meters per square second.19395878Sfc1 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
20 J/kg
Mixed-layer CIN
-85 J/kg
Mixed-layer LCL
1604 m above ground
0-6 km bulk shear
23 kt
0-1 km storm-relative helicity
-14 m²/s²
0-3 km storm-relative helicity
12 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

026 
WGUS51 KRNK 050239
FFWRNK
WVC055-089-050845-
/O.NEW.KRNK.FF.W.0026.210805T0239Z-210805T0845Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Blacksburg VA
1039 PM EDT Wed Aug 4 2021

The National Weather Service in Blacksburg has issued a

* Flash Flood Warning for...
  Western Mercer County in southeastern West Virginia...
  West Central Summers County in southeastern West Virginia...

* Until 445 AM EDT Thursday.

* At 1039 PM EDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the western part of Mercer county near and along 
  to just east of the Raleigh and Wyoming County lines.  This 
  includes areas near Camp Creek State Park, Winonah, and Flat Top. 
  Between 2.5 and 4 inches of rain have fallen to the west of these 
  areas during the past 1 to 2 hours. The expected rainfall rate is 
  1.5 to 2 inches in 30 minutes. Additional rainfall amounts of 1.5 
  to 3 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...
  Matoaka...                         Camp Creek...
  Bramwell...                        Camp Creek State Park...
  Spanishburg...                     Wenonah...
  Flat Top...

This includes the following streams and drainages...
  Bluestone River, Flipping Creek, Camp Creek, Crane Creek, Big 
  Branch and Clark Branch.

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.

In hilly terrain there are hundreds of low water crossings which are 
potentially dangerous in heavy rain. Do not attempt to cross flooded 
roads. Find an alternate route.

When it is safe to do so, please send your reports of flooding, 
including mudslides or flooded roads, to the National Weather 
Service by calling toll free at 1...8 6 6...2 1 5...4 3 2 4. Reports 
and pictures can also be shared on the National Weather Service 
Blacksburg Facebook page and on Twitter.

&&

LAT...LON 3759 8109 3761 8106 3763 8106 3764 8106
      3765 8103 3765 8098 3765 8095 3750 8106
      3728 8127 3734 8136 3742 8131 3740 8129
      3742 8128 3746 8131 3747 8128 3750 8126
      3751 8120 3754 8120 3758 8120 3760 8114

FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL...1.5-2 INCHES IN 29 MINUTES

$$

RAB
2 follow-up statements
469 
WGUS71 KRNK 050330
FFSRNK

Flash Flood Statement
National Weather Service Blacksburg VA
1130 PM EDT Wed Aug 4 2021

WVC089-050340-
/O.CAN.KRNK.FF.W.0026.000000T0000Z-210805T0845Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Summers WV-
1130 PM EDT Wed Aug 4 2021

...FLASH FLOOD WARNING IS CANCELLED FOR WEST CENTRAL SUMMERS 
COUNTY...

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

LAT...LON 3754 8103 3728 8127 3734 8136 3742 8131
      3740 8129 3742 8128 3746 8131 3747 8128
      3750 8126 3751 8120 3758 8120 3760 8114
      3759 8112 3759 8111

$$

WVC055-050845-
/O.CON.KRNK.FF.W.0026.000000T0000Z-210805T0845Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Mercer WV-
1130 PM EDT Wed Aug 4 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 445 AM EDT THURSDAY 
FOR WESTERN MERCER COUNTY...

At 1130 PM EDT, Doppler radar indicated thunderstorms have weakened 
across western Mercer County,but runoff from 3 to 5 inches of rain 
that fell will likely continue to cause flooding. Additional 
rainfall amounts of 0.5 to 1 inch are possible in the warned area.

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...
  Matoaka...
Wenonah...                          
Camp Creek...

This includes the following streams and drainages...
Flipping Creek, Glade Branch, Camp Creek, Crane Creek, Big Branch 
and Clark Branch.

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.

In hilly terrain there are hundreds of low water crossings which are 
potentially dangerous in heavy rain. Do not attempt to cross flooded 
roads. Find an alternate route.

When it is safe to do so, please send your reports of flooding, 
including mudslides or flooded roads, to the National Weather 
Service by calling toll free at 1...8 6 6...2 1 5...4 3 2 4. Reports 
and pictures can also be shared on the National Weather Service 
Blacksburg Facebook page and on Twitter.

&&

LAT...LON 3754 8103 3728 8127 3734 8136 3742 8131
      3740 8129 3742 8128 3746 8131 3747 8128
      3750 8126 3751 8120 3758 8120 3760 8114
      3759 8112 3759 8111

FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL...0.5-1 INCH IN 1 HOUR

$$

PH
119 
WGUS71 KRNK 050613
FFSRNK

Flash Flood Statement
National Weather Service Blacksburg VA
213 AM EDT Thu Aug 5 2021

WVC055-050623-
/O.CAN.KRNK.FF.W.0026.000000T0000Z-210805T0845Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Mercer WV-
213 AM EDT Thu Aug 5 2021

...FLASH FLOOD WARNING IS CANCELLED FOR WESTERN MERCER COUNTY...

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

LAT...LON 3754 8103 3728 8127 3734 8136 3742 8131
      3740 8129 3742 8128 3746 8131 3747 8128
      3750 8126 3751 8120 3758 8120 3760 8114
      3759 8112 3759 8111

$$

PH

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 4, 10:10 PM EDTSpecial Weather StatementRNKMercer50 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.