Alert archive / South Carolina / Flash Flood Warnings in 2011

Flash Flood Warning 7, NWS Charleston, SC

August 6, 2011Berkeley County, Charleston County, Dorchester County, South Carolina

NWS Charleston, SC issued this flash flood warning at Aug 6, 2011, 3:31 PM EDT for Berkeley County, Charleston County, Dorchester County, South Carolina. It was in force for 49 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: Aug 6, 2011, 3:31 PM EDT (19:31 UTC)
Expired: Aug 6, 2011, 4:20 PM EDT
In force: 49 min
Issued by: NWS Charleston, SC
Area: Storm-based polygon
Flood severity: None

Counties Berkeley County, SC, Charleston County, SC, Dorchester County, SC

The radar

The Charleston,SC radar (KCLX), 79 km from the middle of the area, began a volume at 19:34 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

Charleston AFB, SC (KCHS), launched 12:00Z, 7.5 hours before the alert went out and 22 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: 1719 J/kg
Mixed-layer CIN: -32 J/kg
Mixed-layer LCL: 697 m above ground
0-6 km bulk shear: 13 kt
0-1 km storm-relative helicity: -29 m²/s²
0-3 km storm-relative helicity: -3 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.

884 
WGUS52 KCHS 061931
FFWCHS
SCC015-019-035-062130-
/O.NEW.KCHS.FF.W.0007.110806T1931Z-110806T2130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE CHARLESTON SC
331 PM EDT SAT AUG 6 2011

THE NATIONAL WEATHER SERVICE IN CHARLESTON HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  SOUTH CENTRAL BERKELEY COUNTY IN SOUTHEAST SOUTH CAROLINA...
  WEST CENTRAL CHARLESTON COUNTY IN SOUTHEAST SOUTH CAROLINA...
  SOUTHEASTERN DORCHESTER COUNTY IN SOUTHEAST SOUTH CAROLINA...

* UNTIL 530 PM EDT

* AT 330 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED   
  NEARLY STATIONARY THUNDERSTORMS PRODUCING TORRENTIAL               
  RAINFALL...WITH THE HEAVIEST RAIN OCCURRING NEAR MIDDLETON PLACE.  

  RADAR ESTIMATES THAT 3 TO 5 INCHES OF RAIN HAS ALREADY OCCURRED OVER 
  PARTS OF THE WARNING AREA...WITH LOCALLY HIGHER AMOUNTS AROUND 6 
  INCHES BETWEEN COOKE CROSSROADS AND MIDDLETON PLACE. AN ADDITIONAL 1 
  TO 3 INCHES OF RAIN WITH LOCALLY HIGHER AMOUNTS IS EXPECTED THROUGH 
  530 PM. 

* FLASH FLOODING IS EXPECTED IN AND AROUND...
  DELEMAR CROSSROADS...RAVENEL...MIDDLETON PLACE...ARCHDALE...
  NORTHWOODS MALL...COLLEGE PARK

PRECAUTIONARY/PREPAREDNESS ACTIONS...

AVOID DRIVING INTO WATER ON THE ROAD. THE WATER IS USUALLY DEEPER
THAN IT APPEARS AND THE ROAD MAY BE WASHED OUT. ONLY ONE FOOT OF
WATER WILL STALL A VEHICLE AND LESS THAN TWO FEET OF WATER CAN FLOAT
AND CARRY AWAY A VEHICLE. FLOODING IS THE NUMBER ONE WEATHER-RELATED
CAUSE OF DEATH IN THE UNITED STATES. WHEN ENCOUNTERING FLOODED ROADS
MAKE THE SMART CHOICE...TURN AROUND...DONT DROWN.

TO REPORT FLOODING...CONTACT THE NATIONAL WEATHER SERVICE IN
CHARLESTON TOLL FREE AT 1-888-383-2024.

&&

LAT...LON 3287 8040 3304 8010 3291 7999 3272 8031

$$

JAQ

1 follow-up statement

381 
WGUS72 KCHS 062020
FFSCHS

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE CHARLESTON SC
420 PM EDT SAT AUG 6 2011

SCC015-019-035-062029-
/O.CAN.KCHS.FF.W.0007.000000T0000Z-110806T2130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
DORCHESTER SC-CHARLESTON SC-BERKELEY SC-
420 PM EDT SAT AUG 6 2011

...THE FLASH FLOOD WARNING HAS BEEN CANCELLED FOR SOUTH CENTRAL
BERKELEY...WEST CENTRAL CHARLESTON AND SOUTHEASTERN DORCHESTER
COUNTIES...

AT 419 PM...NATIONAL WEATHER SERVICE RADAR INDICATED THAT THE 
HEAVIEST RAINFALL HAS ENDED...THEREFORE THE FLASH FLOOD WARNING HAS 
BEEN CANCELLED. 

ALTHOUGH THE SIGNIFICANT FLOODING HAS ENDED...DRAINAGE SYSTEMS AND
CULVERTS WILL REMAIN FULL. PONDING WATER WILL PERSIST IN LOW-LYING
AREAS AND MAY POSE A HAZARD TO MOTORISTS. STAY TUNED TO NOAA WEATHER
RADIO ALL-HAZARDS FOR THE LATEST WEATHER INFORMATION.

TO REPORT SIGNIFICANT FLOODING...PLEASE CONTACT THE NATIONAL WEATHER
SERVICE IN CHARLESTON TOLL FREE AT 1-888-383-2024 OR EMAIL YOUR
REPORTS TO CHS.SKYWARN@NOAA.GOV. REPORTS CAN ALSO BE SENT THROUGH
TWITTER USING #WXREPORT.

LAT...LON 3287 8040 3304 8010 3291 7999 3272 8031

$$

JAQ

The office that day

Everything else NWS Charleston, SC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Aug 5, 10:03 PM EDT	Special Weather Statement	CHS	Hampton	42 min
Aug 6, 2:28 PM EDT	Areal Flood Advisory	CHS	Berkeley, Charleston, Dorchester	2 hr
Aug 6, 3:17 PM EDT	Areal Flood Advisory	CHS	Colleton	118 min
Aug 6, 4:00 PM EDT	Heat Advisory	CHS	Allendale, Berkeley, Colleton, Dorchester, Hampton	27 hr
Aug 6, 4:29 PM EDT	Special Weather Statement	CHS	Jasper	31 min
Aug 6, 4:47 PM EDT	Severe Thunderstorm Warning	CHS	Colleton, Hampton	39 min
Aug 6, 5:59 PM EDT	Special Weather Statement	CHS	Hampton	31 min

Nearby

Flash Flood Warnings in South 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.