Alert archive / Virginia / Flash Flood Warnings in 2011

Flash Flood Warning 26, NWS Blacksburg, VA

May 16, 2011Patrick County, Virginia

NWS Blacksburg, VA issued this flash flood warning at May 16, 2011, 9:48 PM EDT for Patrick County, Virginia. It was in force for 6 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
May 16, 2011, 9:48 PM EDT (01:48 UTC)
Expired
May 17, 2011, 3:45 AM EDT
In force
6 hr
Issued by
NWS Blacksburg, VA
Area
Storm-based polygon
Flood severity
None

County Patrick County, VA

The radar

The Roanoke radar (KFCX), 36 km from the middle of the area, began a volume at 01:51 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

Greensboro/Hi Pt, NC (KGSO), launched 00:00Z, 1.8 hours before the alert went out and 74 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, Greensboro/Hi Pt, NC at 00:00Z on 2011-05-17Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 639 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, Greensboro/Hi Pt, NC at 00:00Z on 2011-05-17The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -1 square meters per square second.193958Sfc1 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
639 J/kg
Mixed-layer CIN
-7 J/kg
Mixed-layer LCL
785 m above ground
0-6 km bulk shear
23 kt
0-1 km storm-relative helicity
-1 m²/s²
0-3 km storm-relative helicity
0 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

752 
WGUS51 KRNK 170148
FFWRNK
VAC141-170745-
/O.NEW.KRNK.FF.W.0026.110517T0148Z-110517T0745Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE BLACKSBURG VA
948 PM EDT MON MAY 16 2011

THE NATIONAL WEATHER SERVICE IN BLACKSBURG HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  EASTERN PATRICK COUNTY IN SOUTHWEST VIRGINIA

* UNTIL 345 AM EDT.

* AT 942 PM EDT...TRAINED WEATHER SPOTTERS REPORTED TWO INCHES OF    
  RAIN HAD FALLEN IN ABOUT AN HOUR AND A HALF.

* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO WOOLWINE...
  CHARITY AND BUFFALO RIDGE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

SPRING ROAD AND ANIMAL CLINIC ROAD ARE PRONE TO FLOODING. 

ADDITIONAL RAINFALL AMOUNTS OF AN INCH ARE POSSIBLE IN THE WARNED 
AREA.

EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF SMALL
CREEKS AND STREAMS...COUNTRY ROADS...AS WELL AS FARMLAND ALONG THE
BANKS OF CREEKS AND STREAMS.

DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE
ROADWAY. THE WATER DEPTH MAY BE TOO GREAT TO ALLOW YOUR CAR TO CROSS
SAFELY. MOVE TO HIGHER GROUND.

PLEASE RELAY ANY REPORTS OF FLOODING INCLUDING MUDSLIDES...OR ROAD
CLOSURES TO THE NATIONAL WEATHER SERVICE IN BLACKSBURG BY CALLING
TOLL FREE...1...8 6 6...2 1 5...4 3 2 4. DELAYED REPORTS ARE WELCOME.

&&

LAT...LON 3656 8036 3682 8034 3687 8022 3682 8008
      3678 8008 3678 8010 3662 8006 3655 8008

$$
1 follow-up statement
938 
WGUS71 KRNK 170314
FFSRNK

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE BLACKSBURG VA
1114 PM EDT MON MAY 16 2011

VAC141-170745-
/O.CON.KRNK.FF.W.0026.000000T0000Z-110517T0745Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
PATRICK VA-
1114 PM EDT MON MAY 16 2011

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 345 AM EDT FOR
EASTERN PATRICK COUNTY...

AT 1105 PM EDT...HEAVIER RAINFALL HAD BRIEFLY TAPERED OFF ACROSS THE 
WARNED AREA. HOWEVER NATIONAL WEATHER SERVICE DOPPLER RADAR 
CONTINUED TO SHOW MORE SHOWERS AND THUNDERSTORMS APPROACHING FROM 
THE SOUTHEAST AND THESE WILL OVERSPREAD THE REGION AROUND MIDNIGHT. 
THESE SHOWERS WILL AGAIN BRING ANOTHER ROUND OF MODERATE TO HEAVY 
RAINFALL INTO THE EARLY MORNING HOURS OF TUESDAY.

LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO ROCKY KNOB 
RECREATION AREA...WOOLWINE...CHARITY AND BUFFALO RIDGE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

ADDITIONAL RAINFALL AMOUNTS OF 1 TO PERHAPS 2 INCHES ARE POSSIBLE IN 
THE WARNED AREA.

EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF SMALL
CREEKS AND STREAMS...COUNTRY ROADS...AS WELL AS FARMLAND ALONG THE
BANKS OF CREEKS AND STREAMS.

BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO RECOGNIZE THE
DANGERS OF FLOODING. IF FLASH FLOODING IS OBSERVED ACT QUICKLY. MOVE
UP TO HIGHER GROUND TO ESCAPE FLOOD WATERS. DO NOT STAY IN AREAS
SUBJECT TO FLOODING WHEN WATER BEGINS RISING.

&&

LAT...LON 3656 8036 3682 8034 3687 8022 3682 8008
      3678 8008 3678 8010 3662 8006 3655 8008

$$

JH

The office that day

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

IssuedProductOfficeCountiesLasted
May 16, 11:22 PM EDTSpecial Weather StatementRNKHenry, City of Martinsville53 min
May 17, 12:49 AM EDTSpecial Weather StatementRNKCity of Roanoke56 min
May 17, 12:53 AM EDTSpecial Weather StatementRNKFranklin67 min
May 17, 2:07 AM EDTSpecial Weather StatementRNKRoanoke, City of Roanoke, City of Salem53 min
May 17, 4:03 AM EDTFlash Flood WatchRNKAlleghany, Amherst, Bath, Bedford, Botetourt, Campbell and 19 more24 hr
May 17, 11:03 AM EDTSpecial Weather StatementRNKFloyd, Franklin57 min
May 17, 1:20 PM EDTSpecial Weather StatementRNKCity of Roanoke, City of Salem40 min
May 17, 2:24 PM EDTSpecial Weather StatementRNKCharlotte51 min
May 17, 3:51 PM EDTSpecial Weather StatementRNKPatrick24 min
May 17, 4:55 PM EDTSpecial Weather StatementRNKAlleghany, City of Covington50 min

Nearby

Flash Flood Warnings in Virginia, 2011Every flash flood warning in 2011

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.