Alert archive / North Carolina / Flash Flood Warnings in 2011

Flash Flood Warning 3, NWS Raleigh, NC

May 11, 2011Anson County, North Carolina

NWS Raleigh, NC issued this flash flood warning at May 11, 2011, 2:47 AM EDT for Anson County, North Carolina. 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 11, 2011, 2:47 AM EDT (06:47 UTC)
Expired: May 11, 2011, 5:45 AM EDT
In force: 3 hr
Issued by: NWS Raleigh, NC
Area: Storm-based polygon
Flood severity: None

County Anson County, NC

The radar

The Raleigh/Durham radar (KRAX), 155 km from the middle of the area, began a volume at 06:50 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, 6.8 hours before the alert went out and 119 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: 694 J/kg
Mixed-layer CIN: -146 J/kg
Mixed-layer LCL: 1286 m above ground
0-6 km bulk shear: 50 kt
0-1 km storm-relative helicity: 109 m²/s²
0-3 km storm-relative helicity: 420 m²/s²
Significant tornado parameter: 0.3
Supercell composite: 11.6

Open this sounding in Storm Lab

The text

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

449 
WGUS52 KRAH 110647
FFWRAH
NCC007-110945-
/O.NEW.KRAH.FF.W.0003.110511T0647Z-110511T0945Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE RALEIGH NC
247 AM EDT WED MAY 11 2011

THE NATIONAL WEATHER SERVICE IN RALEIGH HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  ANSON COUNTY IN CENTRAL NORTH CAROLINA

* UNTIL 545 AM EDT

* AT 241 AM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  THUNDERSTORMS WITH VERY HEAVY RAIN PRODUCING FLOODING OVER ANSON   
  COUNTY. DOPPLER RADAR ESTIMATED THAT TWO AND A HALF TO OVER THREE  
  INCHES OF RAIN HAS FALLEN OVER WESTERN AND SOUTHERN ANSON COUNTY.

* LOCATIONS THREATENED WITH FLOODING INCLUDE AREAS ALONG BROWN CREEK 
  INCLUDING... POLKTON AND ANSONVILLE. HEAVY RAINFALL MAY ALSO CAUSE 
  FLOODING ALONG CREEKS AND STREAMS IN SOUTHERN ANSON COUNTY.

AN ADDITIONAL TENTH TO A QUARTER OF AN INCH OF RAINFALL IS STILL 
POSSIBLE RESULTING IN ADDITIONAL FLOODING.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

EXCESSIVE RUNOFF FROM THE HEAVY RAIN WILL CAUSE FLASH FLOODING OF
CREEKS AND STREAMS...ROADS...LOW LYING AND POOR DRAINAGE AREAS. DO
NOT DRIVE YOUR VEHICLE INTO AREAS WHERE WATER COVERS THE ROAD. MANY
ROADS AND INTERSECTIONS IN THE AREA WILL QUICKLY FLOOD. WHEN
ENCOUNTERING FLOODED ROADS TURN AROUND...DONT DROWN.

BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO RECOGNIZE THE
DANGERS OF FLOODS AND FLASH FLOODS. 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.

PLEASE REPORT FLOODING TO THE NATIONAL WEATHER SERVICE BY CALLING...
1...8 7 7...6 3 3...6 7 7 2 OR NOTIFY YOUR LOCAL LAW ENFORCEMENT
AGENCY.

&&

LAT...LON 3512 8029 3513 8007 3511 8006 3508 8000
      3512 7995 3511 7992 3506 7991 3505 7988
      3501 7990 3498 7987 3495 7987 3490 7985
      3485 7990 3480 7992 3481 8033

$$

KC

2 follow-up statements

761 
WGUS72 KRAH 110805
FFSRAH

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE RALEIGH NC
405 AM EDT WED MAY 11 2011

NCC007-110945-
/O.CON.KRAH.FF.W.0003.000000T0000Z-110511T0945Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
ANSON NC-
405 AM EDT WED MAY 11 2011

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 545 AM EDT FOR ANSON
COUNTY...

AT 353 AM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO 
INDICATE MODERATE RAIN FALLING ACROSS SOUTHERN ANSON COUNTY.  
DOPPLER RADAR ESTIMATED THAT 3 TO 4 INCHES OF RAIN HAS FALLEN OVER 
THE PAST 3 HOURS...WITH AS MUCH AS AN INCH IN THE PAST HOUR. 
WHILE RAINFALL SHOULD BEGIN TO DIMINISH ACROSS THE WARNING AREA OVER 
THE NEXT HALF AN HOUR...EXCESSIVE RUNOFF WILL CONTINUE TO CAUSE 
FLOODING IN SOME LOCATIONS. 

LOCATIONS THREATENED WITH FLOODING INCLUDE AREAS ALONG BROWN CREEK   
INCLUDING... WADESBORO AND MORVEN. HEAVY RAINFALL MAY ALSO CAUSE   
FLOODING ALONG CREEKS AND STREAMS IN SOUTHERN ANSON COUNTY.


PRECAUTIONARY/PREPAREDNESS ACTIONS...

EXCESSIVE RUNOFF FROM THE HEAVY RAIN WILL CAUSE FLASH FLOODING OF
CREEKS AND STREAMS...ROADS...LOW LYING AND POOR DRAINAGE AREAS. DO
NOT DRIVE YOUR VEHICLE INTO AREAS WHERE WATER COVERS THE ROAD. MANY
ROADS AND INTERSECTIONS IN THE AREA WILL QUICKLY FLOOD. WHEN
ENCOUNTERING FLOODED ROADS TURN AROUND...DONT DROWN.

PLEASE REPORT FLOODING TO THE NATIONAL WEATHER SERVICE BY CALLING...
1...8 7 7...6 3 3...6 7 7 2 OR NOTIFY YOUR LOCAL LAW ENFORCEMENT
AGENCY.

&&

LAT...LON 3512 8029 3513 8007 3511 8006 3508 8000
      3512 7995 3511 7992 3506 7991 3505 7988
      3501 7990 3498 7987 3495 7987 3490 7985
      3485 7990 3480 7992 3481 8033

$$

23

481 
WGUS72 KRAH 110941
FFSRAH

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE RALEIGH NC
541 AM EDT WED MAY 11 2011

NCC007-110949-
/O.EXP.KRAH.FF.W.0003.000000T0000Z-110511T0945Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
ANSON NC-
541 AM EDT WED MAY 11 2011

...THE FLASH FLOOD WARNING WILL EXPIRE AT 545 AM EDT FOR ANSON
COUNTY...

THE HEAVY RAIN HAS MOVED OUT OF THE WARNED AREA AND NO FLOODING HAS 
BEEN REPORTED. THEREFORE...THE FLASH FLOOD WARNING WILL BE ALLOWED 
TO EXPIRE. 

LAT...LON 3512 8029 3513 8007 3511 8006 3508 8000
      3512 7995 3511 7992 3506 7991 3505 7988
      3501 7990 3498 7987 3495 7987 3490 7985
      3485 7990 3480 7992 3481 8033

$$

KRR

The office that day

Everything else NWS Raleigh, NC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
May 10, 9:34 PM EDT	Special Weather Statement	RAH	Person	26 min
May 10, 11:02 PM EDT	Special Weather Statement	RAH	Richmond	28 min
May 10, 11:20 PM EDT	Special Weather Statement	RAH	Harnett, Wake	40 min
May 11, 12:27 AM EDT	Special Weather Statement	RAH	Anson, Stanly	63 min
May 11, 12:53 AM EDT	Special Weather Statement	RAH	Montgomery, Richmond	52 min
May 11, 1:32 AM EDT	Special Weather Statement	RAH	Anson	58 min
May 11, 1:37 AM EDT	Special Weather Statement	RAH	Scotland	53 min
May 11, 2:03 AM EDT	Areal Flood Advisory	RAH	Anson	69 min
May 11, 2:11 AM EDT	Areal Flood Advisory	RAH	Scotland	109 min

Nearby

Flash Flood Warnings in North Carolina, 2011 Every 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.