Alert archive / North Carolina / Flash Flood Warnings in 2011

Flash Flood Warning 10, NWS Raleigh, NC

June 11, 2011Guilford County, North Carolina

NWS Raleigh, NC issued this flash flood warning at Jun 11, 2011, 5:40 PM EDT for Guilford County, North Carolina. It was in force for 2 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
Jun 11, 2011, 5:40 PM EDT (21:40 UTC)
Expired
Jun 11, 2011, 7:45 PM EDT
In force
2 hr
Issued by
NWS Raleigh, NC
Area
Storm-based polygon
Flood severity
None

County Guilford County, NC

The radar

The Roanoke radar (KFCX), 116 km from the middle of the area, began a volume at 21:42 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
Jun 11, 5:50 PM EDTFLASH FLOODGreensboro, NCWIDESPREAD FLASH FLOODING IN EAST GREENSBORO. AT LEAST 15 WATER RESCUES UNDERWAY. A COUPLE OF APARTMENT COMPLEXES ALSO BEING EVACUATED.
Jun 11, 6:45 PM EDTFLASH FLOODGreensboro, NCENDING OF FLASH FLOODING IN GREENSBORO. EMERGENCY MANAGEMENT REPORTED URBAN FLOODING ABATED AROUND THIS TIME.

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

The nearest sounding before it

Greensboro/Hi Pt, NC (KGSO), launched 12:00Z, 9.7 hours before the alert went out and 16 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 12:00Z on 2011-06-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 574 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 12:00Z on 2011-06-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 28 square meters per square second.1939Sfc1 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
574 J/kg
Mixed-layer CIN
-118 J/kg
Mixed-layer LCL
1033 m above ground
0-6 km bulk shear
5 kt
0-1 km storm-relative helicity
28 m²/s²
0-3 km storm-relative helicity
30 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.

542 
WGUS52 KRAH 112140
FFWRAH
NCC081-112345-
/O.NEW.KRAH.FF.W.0010.110611T2140Z-110611T2345Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE RALEIGH NC
540 PM EDT SAT JUN 11 2011

THE NATIONAL WEATHER SERVICE IN RALEIGH HAS ISSUED A

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

* UNTIL 745 PM EDT

* AT 536 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  THUNDERSTORMS WITH VERY HEAVY RAIN PRODUCING FLOODING OVER GUILFORD
  COUNTY. DOPPLER RADAR ESTIMATED THAT AROUND TWO INCHES OF RAIN HAS 
  FALLEN QUICKLY IN PARTS OF GREENSBORO NEAR THE DOWNTOWN. ANOTHER 
  TWO INCHES IS POSSIBLE QUICKLY BETWEEN 545 PM AND 630 PM.

* LOCATIONS THREATENED WITH FLOODING INCLUDE MCLEANSVILLE...HIGH   
  POINT AND GREENSBORO.

A REPORT FROM A SPOTTER NOTED THAT SOME WATER WAS STARTED TO 
THREATEN A RESIDENCE OR TWO IN GREENSBORO.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

FLASH FLOODING IS EXTREMELY DANGEROUS. NUMEROUS ROADS AND LOW LYING
AREAS WILL QUICKLY FLOOD. FLOOD WATERS WILL ALSO THREATEN SOME HOMES
AND BUSINESSES. IF YOU ARE EXPERIENCING FLOODING OR LIVE IN A FLOOD
PRONE AREA MOVE TO HIGHER GROUND.

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 3625 7954 3590 7954 3590 7964 3592 8004
      3626 8003

$$

DJF
2 follow-up statements
195 
WGUS72 KRAH 112211
FFSRAH

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE RALEIGH NC
611 PM EDT SAT JUN 11 2011

NCC081-112345-
/O.CON.KRAH.FF.W.0010.000000T0000Z-110611T2345Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
GUILFORD NC-
611 PM EDT SAT JUN 11 2011

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 745 PM EDT FOR
GUILFORD COUNTY...

AT 606 PM EDT...LOCAL EMERGENCY MANAGEMENT REPORTED THUNDERSTORMS
WITH VERY HEAVY RAIN PRODUCING FLASH FLOODING OVER GUILFORD COUNTY. 
AN ESTIMATED FIFTEEN WATER RESCUES HAD OCCURRED FROM PERSONS 
STRANDED IN HIGH WATER IN GREENSBORO...AND A COUPLE OF APARTMENT 
COMPLEXES WERE BEING EVACUATED DUE TO RISING WATER. DOPPLER RADAR 
ESTIMATED THAT THREE TO POSSIBLY FOUR INCHES OF RAIN LIKELY HAD 
OCCURRED ON THE EAST SIDE OF GREENSBORO...AND TOWARD 
MCLEANSVILLE...BETWEEN 5 PM AND 6 PM.

AN ADDITIONAL INCH OF RAIN MAY OCCUR BETWEEN 615 PM AND 7 PM. THE 
DANGERS OF FLASH FLOODING WILL CONTINUE EARLY THIS EVENING AT LEAST 
THROUGH 730 PM. AGAIN...LOCATIONS THREATENED BY FLOODING INCLUDE BUT 
ARE NOT LIMITED TO MCLEANSVILLE AND GREENSBORO.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

EXCESSIVE RUNOFF FROM HEAVY RAINFALL WAS CAUSING FLOODING OF 
SMALL CREEKS AND STREAMS...URBAN AREAS...HIGHWAYS...STREETS AND 
UNDERPASSES AS WELL AS OTHER DRAINAGE AREAS AND LOW LYING SPOTS. DO 
NOT DRIVE WHERE WATER COVERS THE ROAD. AVOID STREAMS AND DITCHES 
RUNNING HIGH AND FLOWING FAST.

&&

LAT...LON 3625 7954 3590 7954 3590 7964 3592 8004
      3626 8003

$$

DJF
134 
WGUS72 KRAH 112343
FFSRAH

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE RALEIGH NC
743 PM EDT SAT JUN 11 2011

NCC081-112350-
/O.EXP.KRAH.FF.W.0010.000000T0000Z-110611T2345Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
GUILFORD NC-
743 PM EDT SAT JUN 11 2011

...THE FLASH FLOOD WARNING WILL EXPIRE AT 745 PM EDT FOR GUILFORD
COUNTY...

AT 737 PM EDT...GUILFORD COUNTY EMERGENCY MANAGEMENT REPORTED THAT 
FLASH FLOODING HAD ABATED IN THE CITY OF GREENSBORO. IN ADDITION...
OBSERVATIONS FROM CREEKS RUNNING HIGH...SUCH AS NORTH BUFFALO 
CREEK...SHOWED RISES SLOWING BELOW THE LOCAL FLOOD STAGE. WHILE 
SCATTERED SHOWERS AND POSSIBLY A THUNDERSTORM OR TWO ARE STILL 
POSSIBLE THIS EVENING...FLASH FLOODING IS NO LONGER EXPECTED. AS A 
RESULT...THE FLASH FLOOD WARNING WILL BE ALLOWED TO EXPIRE.

STAY TUNED TO THIS STATION FOR THE LATEST WEATHER INFORMATION.

LAT...LON 3625 7954 3590 7954 3590 7964 3592 8004
      3626 8003

$$

DJF

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 10, 8:45 PM EDTSpecial Weather StatementRAHDurham45 min
Jun 10, 8:54 PM EDTSpecial Weather StatementRAHRandolph66 min
Jun 10, 9:07 PM EDTSpecial Weather StatementRAHJohnston38 min
Jun 10, 9:09 PM EDTSpecial Weather StatementRAHRandolph66 min
Jun 10, 9:40 PM EDTSpecial Weather StatementRAHFranklin80 min
Jun 10, 9:51 PM EDTAreal Flood AdvisoryRAHEdgecombe, Johnston, Wilson3 hr
Jun 10, 10:01 PM EDTAreal Flood AdvisoryRAHDurham, Franklin, Granville, Wake3 hr
Jun 10, 10:45 PM EDTSpecial Weather StatementRAHDurham60 min
Jun 10, 10:50 PM EDTSpecial Weather StatementRAHMoore55 min
Jun 10, 11:08 PM EDTSpecial Weather StatementRAHLee67 min
Jun 10, 11:26 PM EDTSpecial Weather StatementRAHWake64 min
Jun 10, 11:41 PM EDTSpecial Weather StatementRAHLee64 min
Jun 11, 2:34 PM EDTSpecial Weather StatementRAHDavidson41 min
Jun 11, 3:12 PM EDTSpecial Weather StatementRAHDavidson48 min
Jun 11, 3:26 PM EDTSpecial Weather StatementRAHMontgomery49 min
Jun 11, 3:38 PM EDTSpecial Weather StatementRAHForsyth112 min
Jun 11, 3:58 PM EDTSpecial Weather StatementRAHMontgomery, Stanly62 min
Jun 11, 4:09 PM EDTSevere Thunderstorm WarningRAHMontgomery, Stanly51 min
Jun 11, 4:34 PM EDTSpecial Weather StatementRAHDavidson56 min
Jun 11, 4:36 PM EDTSpecial Weather StatementRAHForsyth54 min
Jun 11, 5:06 PM EDTSpecial Weather StatementRAHMontgomery54 min
Jun 11, 5:21 PM EDTSevere Thunderstorm WarningRAHGuilford38 min
Jun 11, 5:29 PM EDTAreal Flood AdvisoryRAHGuilford2 hr
Jun 11, 5:45 PM EDTSpecial Weather StatementRAHMoore60 min
Jun 11, 5:53 PM EDTSpecial Weather StatementRAHAlamance52 min
Jun 11, 5:55 PM EDTAreal Flood AdvisoryRAHAlamance, Orange, Person3 hr
Jun 11, 6:15 PM EDTSpecial Weather StatementRAHPerson60 min
Jun 11, 6:17 PM EDTSpecial Weather StatementRAHDurham, Orange58 min
Jun 11, 6:25 PM EDTAreal Flood AdvisoryRAHMoore48 min
Jun 11, 6:35 PM EDTSpecial Weather StatementRAHGranville55 min
Jun 11, 6:39 PM EDTSevere Thunderstorm WarningRAHDurham, Orange39 min
Jun 11, 6:42 PM EDTSevere Thunderstorm WarningRAHChatham42 min
Jun 11, 6:45 PM EDTSevere Thunderstorm WarningRAHDurham, Granville, Person45 min
Jun 11, 6:59 PM EDTSpecial Weather StatementRAHWake61 min
Jun 11, 7:21 PM EDTSpecial Weather StatementRAHVance54 min
Jun 11, 7:34 PM EDTSpecial Weather StatementRAHFranklin56 min
Jun 11, 7:45 PM EDTSpecial Weather StatementRAHWarren60 min

Nearby

Flash Flood Warnings in North Carolina, 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.