Alert archive / North Carolina / Flash Flood Warnings in 2011

Flash Flood Warning 40, NWS Raleigh, NC

August 21, 20116 counties in North Carolina

NWS Raleigh, NC issued this flash flood warning at Aug 21, 2011, 8:36 PM EDT for 6 counties in North Carolina. It was in force for 4 hr. 2 reports 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 21, 2011, 8:36 PM EDT (00:36 UTC)
Expired: Aug 22, 2011, 1:00 AM EDT
In force: 4 hr
Issued by: NWS Raleigh, NC
Area: Storm-based polygon
Flood severity: None

Counties Durham County, NC, Edgecombe County, NC, Franklin County, NC, Johnston County, NC, Nash County, NC, Wake County, NC

The radar

The Raleigh/Durham radar (KRAX), 42 km from the middle of the area, began a volume at 00:36 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

Time	Report	Where	Remark
Aug 21, 8:50 PM EDT	FLASH FLOOD	4 Ssw Dortches, NC	PARTS OF SOUTH HALIFAX ROAD BETWEEN KETCH POINT DRIVE AND MCINTYRE LANE CLOSED DUE TO HIGH WATER AND PREVIOUS HEAVY RAIN. DOT ENROUTE.
Aug 22, 12:45 AM EDT	FLASH FLOOD	4 S Dortches, NC	LAW ENFORCEMENT REPORTED ALL ROADS...INCLUDING HALIFAX RD...REOPENED AS OF 1245 AM.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Newport, NC (KMHX), launched 00:00Z, 0.6 hours before the alert went out and 162 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: 2006 J/kg
Mixed-layer CIN: -35 J/kg
Mixed-layer LCL: 834 m above ground
0-6 km bulk shear: 22 kt
0-1 km storm-relative helicity: 94 m²/s²
0-3 km storm-relative helicity: 126 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 3.4

Open this sounding in Storm Lab

The text

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

884 
WGUS52 KRAH 220036
FFWRAH
NCC063-065-069-101-127-183-220500-
/O.NEW.KRAH.FF.W.0040.110822T0036Z-110822T0500Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE RALEIGH NC
836 PM EDT SUN AUG 21 2011

THE NATIONAL WEATHER SERVICE IN RALEIGH HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  DURHAM COUNTY IN CENTRAL NORTH CAROLINA
  EDGECOMBE COUNTY IN CENTRAL NORTH CAROLINA
  FRANKLIN COUNTY IN CENTRAL NORTH CAROLINA
  WAKE COUNTY IN CENTRAL NORTH CAROLINA
  NASH COUNTY IN CENTRAL NORTH CAROLINA
  JOHNSTON COUNTY IN CENTRAL NORTH CAROLINA

* UNTIL 100 AM EDT

* AT 831 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  THUNDERSTORMS WITH VERY HEAVY RAIN PRODUCING FLOODING OVER NORTH
  CENTRAL JOHNSTON...NASH...NORTHERN WAKE...SOUTHERN FRANKLIN...
  EDGECOMBE AND SOUTHERN DURHAM COUNTIES. DOPPLER RADAR ESTIMATED   
THAT TWO TO FOUR INCHES OF RAIN HAS FALLEN OVER PORTIONS OF THE 
WARNED AREA

* LOCATIONS THREATENED WITH FLOODING INCLUDE WAKE FOREST...TARBORO...
  ROCKY MOUNT...RDU INTERNATIONAL AIRPORT...RALEIGH...NASHVILLE...
  LOUISBURG...FRANKLINTON...DORTCHES...CARY...BUNN AND BAILEY.

AN ADDITIONAL ONE TO THREE INCHES OF RAINFALL ARE 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 3582 7735 3580 7747 3569 7763 3569 7768
      3582 7775 3587 7783 3584 7785 3584 7790
      3574 7818 3570 7816 3562 7828 3579 7893
      3586 7891 3587 7896 3591 7897 3610 7883
      3602 7855 3615 7850 3599 7740 3587 7734

$$

77

5 follow-up statements

894 
WGUS72 KRAH 220130
FFSRAH

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE RALEIGH NC
930 PM EDT SUN AUG 21 2011

NCC063-220134-
/O.CAN.KRAH.FF.W.0040.000000T0000Z-110822T0500Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
DURHAM NC-
930 PM EDT SUN AUG 21 2011

...THE FLASH FLOOD WARNING HAS BEEN CANCELLED FOR SOUTHERN DURHAM
COUNTY...

HEAVY RAINFALL HAS MOVED OUT OF DURHAM COUNTY AND NO FLOODING HAS 
BEEN REPORTED. THUS... THE FLOODING THREAT HAS ENDED ACROSS DURHAM 
COUNTY.

LAT...LON 3582 7735 3580 7747 3569 7763 3570 7768
      3583 7775 3587 7783 3574 7818 3570 7816
      3562 7828 3582 7887 3594 7872 3605 7867
      3602 7855 3609 7850 3609 7812 3599 7740
      3587 7734

$$

NCC065-069-101-127-183-220500-
/O.CON.KRAH.FF.W.0040.000000T0000Z-110822T0500Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
EDGECOMBE NC-FRANKLIN NC-WAKE NC-NASH NC-JOHNSTON NC-
930 PM EDT SUN AUG 21 2011

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 100 AM EDT FOR NORTH
CENTRAL JOHNSTON...NASH...NORTHERN WAKE...SOUTHERN FRANKLIN AND
EDGECOMBE COUNTIES...

AT 921 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE THUNDERSTORMS WITH VERY HEAVY RAIN OVER NORTH CENTRAL
JOHNSTON...NASH...NORTHERN WAKE...SOUTHERN FRANKLIN AND EDGECOMBE 
COUNTIES. DOPPLER RADAR ESTIMATED THAT AS MUCH AS THREE TO FIVE 
INCHES OF RAIN HAS FALLEN OVER PORTIONS OF THE WARNED AREA.

AN ADDITIONAL ONE TO THREE INCHES OF RAINFALL ARE STILL POSSIBLE 
RESULTING IN ADDITIONAL FLOODING.

LOCATIONS THREATENED BY FLOODING INCLUDE BUT ARE NOT LIMITED TO 
RALEIGH... MIDDLESEX... WENDELL... ROCKY MOUNT... AND PINETOPS.

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 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.

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 3582 7735 3580 7747 3569 7763 3570 7768
      3583 7775 3587 7783 3574 7818 3570 7816
      3562 7828 3582 7887 3594 7872 3605 7867
      3602 7855 3609 7850 3609 7812 3599 7740
      3587 7734

$$

77

310 
WGUS72 KRAH 220201
FFSRAH

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE RALEIGH NC
1001 PM EDT SUN AUG 21 2011

NCC069-101-183-220204-
/O.CAN.KRAH.FF.W.0040.000000T0000Z-110822T0500Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
FRANKLIN NC-WAKE NC-JOHNSTON NC-
1001 PM EDT SUN AUG 21 2011

...THE FLASH FLOOD WARNING HAS BEEN CANCELLED FOR NORTH CENTRAL
JOHNSTON...NORTHERN WAKE AND SOUTHERN FRANKLIN COUNTIES...

HEAVY RAINFALL HAS MOVED OUT OF JOHNSTON... WAKE... AND FRANKLIN 
COUNTIES AND NO FLOODING HAS BEEN REPORTED. THUS... THE FLOODING 
THREAT HAS ENDED.

LAT...LON 3601 7765 3586 7774 3588 7783 3588 7794
      3593 7794 3603 7789

$$

NCC065-127-220500-
/O.CON.KRAH.FF.W.0040.000000T0000Z-110822T0500Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
EDGECOMBE NC-NASH NC-
1001 PM EDT SUN AUG 21 2011

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 100 AM EDT FOR EAST
CENTRAL NASH AND WEST CENTRAL EDGECOMBE COUNTIES...

AT 950 PM EDT...LOCAL LAW ENFORCEMENT REPORTED FLASH FLOODING ALONG 
PARTS OF SOUTH HALIFAX ROAD BETWEEN KETCH POINT DRIVE             
AND MCINTYRE LANE. HEAVY RAIN HAS ENDED ACROSS THE AREA. HOWEVER... 
THE FLOODING THREAT CONTINUES ACROSS PORTIONS OF ROCKY MOUNT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

NEVER DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE ROAD.
AS LITTLE AS 6 INCHES OF WATER CAN CAUSE YOU TO LOSE CONTROL OF YOUR
VEHICLE. TWO FEET OF RUSHING WATER CAN CARRY AWAY MOST VEHICLES
INCLUDING SPORT UTILITY VEHICLES AND PICKUP TRUCKS. TURN AROUND...
DONT DROWN.

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.

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 3601 7765 3586 7774 3588 7783 3588 7794
      3593 7794 3603 7789

$$

77

054 
WGUS72 KRAH 220253
FFSRAH

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE RALEIGH NC
1053 PM EDT SUN AUG 21 2011

NCC065-127-220500-
/O.CON.KRAH.FF.W.0040.000000T0000Z-110822T0500Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
EDGECOMBE NC-NASH NC-
1053 PM EDT SUN AUG 21 2011

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 100 AM EDT FOR EAST
CENTRAL NASH AND WEST CENTRAL EDGECOMBE COUNTIES...

AT 1047 PM EDT...LOCAL LAW ENFORCEMENT REPORTED SOUTH HALIFAX ROAD 
CLOSED BETWEEN KETCH POINT DRIVE AND MCINTYRE LANE. HEAVY RAIN HAS 
ENDED ACROSS THE AREA. STILL...FLOODING MAY STILL BE A CONCERN IN A 
SMALL PART OF ROCKY MOUNT. NATIONAL WEATHER SERVICE DOPPLER RADAR 
INDICATED AS MUCH AS 5 INCHES OF RAIN MAY HAVE FALLEN IN A SMALL 
AREA AROUND AND JUST SOUTH OF ROCKY MOUNT FROM EARLIER 
THUNDERSTORMS. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

DO NOT DRIVE WHERE WATER COVERS THE ROAD. IF A ROAD IS CLOSED...DO 
NOT DRIVE AROUND BARRICADES. 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 3601 7765 3586 7774 3588 7783 3588 7794
      3593 7794 3603 7789

$$

DJF

767 
WGUS72 KRAH 220411
FFSRAH

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE RALEIGH NC
1211 AM EDT MON AUG 22 2011

NCC065-127-220500-
/O.CON.KRAH.FF.W.0040.000000T0000Z-110822T0500Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
EDGECOMBE NC-NASH NC-
1211 AM EDT MON AUG 22 2011

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 100 AM EDT FOR EAST
CENTRAL NASH AND WEST CENTRAL EDGECOMBE COUNTIES...

AT 1208 AM EDT...LOCAL LAW ENFORCEMENT REPORTED NUMEROUS ROADS HAD 
NOT YET REOPENED DUE TO HIGH WATER FROM HEAVY RAIN THAT FELL SUNDAY 
EVENING. 

LOCATIONS THREATENED BY FLOODING INCLUDE BUT ARE NOT LIMITED TO ROCKY
MOUNT AND DORTCHES

PRECAUTIONARY/PREPAREDNESS ACTIONS...

NEVER DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE ROAD.
AS LITTLE AS 6 INCHES OF WATER CAN CAUSE YOU TO LOSE CONTROL OF YOUR
VEHICLE. TWO FEET OF RUSHING WATER CAN CARRY AWAY MOST VEHICLES
INCLUDING SPORT UTILITY VEHICLES AND PICKUP TRUCKS. 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 3601 7765 3586 7774 3588 7783 3588 7794
      3593 7794 3603 7789

$$

MWS

946 
WGUS72 KRAH 220501
FFSRAH

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE RALEIGH NC
101 AM EDT MON AUG 22 2011

NCC065-127-220510-
/O.EXP.KRAH.FF.W.0040.000000T0000Z-110822T0500Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
EDGECOMBE NC-NASH NC-
101 AM EDT MON AUG 22 2011

...THE FLASH FLOOD WARNING HAS EXPIRED FOR EAST CENTRAL NASH AND WEST
CENTRAL EDGECOMBE COUNTIES...

AT 1257 AM EDT...LOCAL LAW ENFORCEMENT REPORTED ALL ROADS... 
INCLUDING HALIFAX ROAD...HAD REOPENED. NO ADDITIONAL FLOODING IS 
EXPECTED. 

LAT...LON 3601 7765 3586 7774 3588 7783 3588 7794
      3593 7794 3603 7789

$$

MWS

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 21, 8:00 PM EDT	Severe Thunderstorm Warning	RAH	Edgecombe, Nash, Wilson	75 min
Aug 21, 8:04 PM EDT	Special Weather Statement	RAH	Anson	56 min
Aug 21, 8:08 PM EDT	Special Weather Statement	RAH	Durham	67 min
Aug 21, 8:12 PM EDT	Severe Thunderstorm Warning	RAH	Franklin, Nash, Wake	69 min
Aug 21, 8:13 PM EDT	Severe Thunderstorm Warning	RAH	Harnett, Lee	62 min
Aug 21, 8:17 PM EDT	Areal Flood Advisory	RAH	Durham, Franklin, Wake	110 min
Aug 21, 8:33 PM EDT	Severe Thunderstorm Warning	RAH	Anson, Montgomery, Richmond	42 min
Aug 21, 8:43 PM EDT	Special Weather Statement	RAH	Wake	62 min
Aug 21, 9:13 PM EDT	Special Weather Statement	RAH	Anson, Hoke, Richmond, Scotland	62 min
Aug 21, 9:30 PM EDT	Special Weather Statement	RAH	Cumberland, Harnett, Johnston, Sampson, Wayne	60 min
Aug 21, 9:37 PM EDT	Areal Flood Advisory	RAH	Harnett	68 min
Aug 21, 9:39 PM EDT	Areal Flood Advisory	RAH	Scotland	3 hr
Aug 21, 10:04 PM EDT	Severe Thunderstorm Warning	RAH	Wayne	37 min
Aug 21, 10:28 PM EDT	Special Weather Statement	RAH	Anson, Richmond, Scotland	62 min
Aug 21, 10:28 PM EDT	Severe Thunderstorm Warning	RAH	Cumberland, Sampson	62 min
Aug 21, 11:40 PM EDT	Special Weather Statement	RAH	Sampson	50 min
Aug 22, 12:34 AM EDT	Areal Flood Advisory	RAH	Cumberland	3 hr

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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.