Alert archive / Virginia / Flash Flood Warnings in 2012

Flash Flood Warning 28, NWS Blacksburg, VA

May 21, 2012Alleghany County, Craig County, Virginia

NWS Blacksburg, VA issued this flash flood warning at May 21, 2012, 6:05 PM EDT for Alleghany County, Craig County, Virginia. It was in force for 3 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 21, 2012, 6:05 PM EDT (22:05 UTC)
Expired: May 21, 2012, 9:00 PM EDT
In force: 3 hr
Issued by: NWS Blacksburg, VA
Area: Storm-based polygon
Flood severity: None

Counties Alleghany County, VA, Craig County, VA

The radar

The Roanoke radar (KFCX), 71 km from the middle of the area, began a volume at 22:06 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

Roanoke, VA (KRNK), launched 12:00Z, 10.1 hours before the alert went out and 72 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 803 m above ground
0-6 km bulk shear: 5 kt
0-1 km storm-relative helicity: -14 m²/s²
0-3 km storm-relative helicity: 76 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.

276 
WGUS51 KRNK 212205
FFWRNK
VAC005-045-220100-
/O.NEW.KRNK.FF.W.0028.120521T2205Z-120522T0100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE BLACKSBURG VA
605 PM EDT MON MAY 21 2012

THE NATIONAL WEATHER SERVICE IN BLACKSBURG HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  NORTHEASTERN CRAIG COUNTY IN SOUTHWEST VIRGINIA
  SOUTHWESTERN ALLEGHANY COUNTY IN WEST CENTRAL VIRGINIA

* UNTIL 900 PM EDT.

* AT 602 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  VERY HEAVY RAIN FROM A THUNDERSTORM NEAR JORDAN MINES IN SOUTHWEST
  ALLEGHANY COUNTY...MOVING SOUTHEAST AT 10 MPH. 

* THE STORM PRODUCING FLASH FLOODING WILL OTHERWISE REMAIN OVER
  MAINLY RURAL AREAS OF THE INDICATED COUNTY.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

RAINFALL OF NEARLY 2.0 INCHES HAS FALLEN IN SOUTHERN ALLEGHANY COUNTY
DURING THE LAST HOUR. ADDITIONAL RAINFALL AMOUNTS OF 1.0 TO 1.5 
INCHES
CAN BE EXPECTED IN THIS SAME AREA DURING THE NEXT 30 TO 60 MINUTES.

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.

A FLASH FLOOD WARNING MEANS THAT FLOODING IS IMMINENT OR OCCURRING.
IF YOU ARE IN THE WARNING AREA MOVE TO HIGHER GROUND IMMEDIATELY.
RESIDENTS LIVING ALONG STREAMS AND CREEKS SHOULD TAKE IMMEDIATE
PRECAUTIONS TO PROTECT LIFE AND PROPERTY. DO NOT ATTEMPT TO CROSS
SWIFTLY FLOWING WATERS OR WATERS OF UNKNOWN DEPTH BY FOOT OR BY
AUTOMOBILE.

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 3778 8016 3765 8001 3763 8003 3756 7998
      3754 7997 3751 8012 3760 8019 3766 8017
      3772 8020

$$



RAB

2 follow-up statements

959 
WGUS71 KRNK 220013
FFSRNK

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE BLACKSBURG VA
813 PM EDT MON MAY 21 2012

VAC005-045-220100-
/O.CON.KRNK.FF.W.0028.000000T0000Z-120522T0100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
CRAIG VA-ALLEGHANY VA-
813 PM EDT MON MAY 21 2012

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 900 PM EDT FOR
NORTHEASTERN CRAIG AND SOUTHWESTERN ALLEGHANY COUNTIES...

AT 757 PM EDT...RAINFALL HAD ENDED ACROSS THE FLASH FLOOD WARNED 
AREA. RAINFALL OF UP TO 3.0 INCHES FELL IN PARTS OF SOUTHERN 
ALLEGHANY AND EXTREME NORTHERN CRAIG COUNTY. THE GROUND IN THIS AREA 
IS COMPLETELY SATURATED FROM RECENT HEAVY RAINFALL. EXCESSIVE RUNOFF 
INTO AREA CREEKS AND STREAMS WILL STILL OCCUR DURING THE NEXT HOUR 
AND MAY RESULT IN FLASH FLOODING ALONG SOME SMALLER CREEKS AND 
STREAMS IN THE AREA...PARTICULARLY ON TOMS BRANCH.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

DO NOT UNDERESTIMATE THE POWER OF FLOOD WATERS. ONLY A FEW INCHES OF 
RAPIDLY FLOWING WATER CAN QUICKLY CARRY AWAY YOUR VEHICLE.

&&

LAT...LON 3778 8016 3765 8001 3763 8003 3756 7998
      3754 7997 3751 8012 3760 8019 3766 8017
      3772 8020

$$

RAB

828 
WGUS71 KRNK 220110
FFSRNK

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE BLACKSBURG VA
910 PM EDT MON MAY 21 2012

VAC005-045-220118-
/O.EXP.KRNK.FF.W.0028.000000T0000Z-120522T0100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
CRAIG VA-ALLEGHANY VA-
910 PM EDT MON MAY 21 2012

...THE FLASH FLOOD WARNING HAS EXPIRED FOR NORTHEASTERN CRAIG AND
SOUTHWESTERN ALLEGHANY COUNTIES...

RAINFALL ACROSS THE PREVIOUSLY WARNED AREA ENDED A COUPLE OF HOURS 
AGO. SO FAR...NO REPORTS OF FLASH FLOODING HAVE BEEN RECEIVED FROM 
THIS AREA AT THIS OFFICE. CREEKS AND STREAMS HAVE HAD SUFFICIENT 
TIME TO DROP BELOW FLOOD LEVELS IN MOST AREAS...BUT SOME MAY REMAIN 
NEAR OR AT BANKFULL FOR THE NEXT FEW HOURS AS RUNOFF OF RAINFALL 
FROM EARLIER HEAVY THUNDERSTORMS CONTINUES ACROSS SOUTHERN ALLEGHANY 
AND NORTHERN CRAIG COUNTIES. 

LAT...LON 3778 8016 3765 8001 3763 8003 3756 7998
      3754 7997 3751 8012 3760 8019 3766 8017
      3772 8020

$$



RAB

The office that day

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

Issued	Product	Office	Counties	Lasted
May 21, 3:53 PM EDT	Special Weather Statement	RNK	Giles	67 min
May 21, 4:38 PM EDT	Special Weather Statement	RNK	Carroll	52 min
May 21, 4:52 PM EDT	Special Weather Statement	RNK	Alleghany, Bath, City of Covington	53 min
May 21, 5:06 PM EDT	Severe Thunderstorm Warning	RNK	Craig, Montgomery	54 min
May 21, 5:33 PM EDT	Special Weather Statement	RNK	Carroll	57 min
May 21, 5:52 PM EDT	Special Weather Statement	RNK	Craig	53 min
May 21, 6:16 PM EDT	Special Weather Statement	RNK	Floyd	59 min
May 21, 6:47 PM EDT	Special Weather Statement	RNK	Botetourt	58 min
May 21, 7:06 PM EDT	Special Weather Statement	RNK	City of Roanoke, City of Salem	54 min
May 21, 7:59 PM EDT	Areal Flood Advisory	RNK	Botetourt	3 hr

Nearby

Flash Flood Warnings in Virginia, 2012 Every flash flood warning in 2012

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.