Alert archive / South Carolina / Flash Flood Warnings in 2012

Flash Flood Warning 11, NWS Charleston, SC

August 29, 2012Allendale County, Colleton County, Hampton County, South Carolina

NWS Charleston, SC issued this flash flood warning at Aug 29, 2012, 9:40 PM EDT for Allendale County, Colleton County, Hampton County, South Carolina. It was in force for 3 hr. 6 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 29, 2012, 9:40 PM EDT (01:40 UTC)
Expired
Aug 30, 2012, 12:45 AM EDT
In force
3 hr
Issued by
NWS Charleston, SC
Area
Storm-based polygon
Flood severity
None

Counties Allendale County, SC, Colleton County, SC, Hampton County, SC

The radar

The Charleston,SC radar (KCLX), 46 km from the middle of the area, began a volume at 01:41 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
Aug 29, 10:05 PM EDTHEAVY RAIN 02 Wnw Fairfax, SCWATER ON HIGHWAY 278. ROAD STILL PASSABLE BUT OFFICERS ARE MONITORING.
Aug 29, 10:18 PM EDTHEAVY RAIN 1.512 Ene Gifford, SC1.51 INCHES OF RAIN MEASURED IN THE PAST 60 MINUTES ALONG WITH MINOR FLOODING.
Aug 29, 10:20 PM EDTFLASH FLOODAllendale, SCHIGHWAY 125 AT 278 CLOSED DUE TO FLOODING.
Aug 29, 10:35 PM EDTFLASH FLOOD1 Sw Allendale, SCFLOODING ON SHORT STREET IN ALLENDALE.
Aug 29, 10:35 PM EDTHEAVY RAIN 0Fairfax, SCMINOR FLOODING ON HIGHWAY 278 IN FAIRFAX. ROAD PASSABLE.
Aug 29, 11:40 PM EDTFLASH FLOODAllendale, SCSEVERAL ROADS IN ALLENDALE REMAIN CLOSED DUE TO FLASH FLOODING.

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

The nearest sounding before it

Jacksonville, FL (KJAX), launched 00:00Z, 1.7 hours before the alert went out and 293 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, Jacksonville, FL at 00:00Z on 2012-08-30Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 749 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, Jacksonville, FL at 00:00Z on 2012-08-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 19 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
749 J/kg
Mixed-layer CIN
-42 J/kg
Mixed-layer LCL
821 m above ground
0-6 km bulk shear
18 kt
0-1 km storm-relative helicity
19 m²/s²
0-3 km storm-relative helicity
21 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.4

Open this sounding in Storm Lab

The text

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

071 
WGUS52 KCHS 300140
FFWCHS
SCC005-029-049-300445-
/O.NEW.KCHS.FF.W.0011.120830T0140Z-120830T0445Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE CHARLESTON SC
940 PM EDT WED AUG 29 2012

THE NATIONAL WEATHER SERVICE IN CHARLESTON HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  EASTERN ALLENDALE COUNTY IN SOUTHEAST SOUTH CAROLINA...
  NORTHWESTERN COLLETON COUNTY IN SOUTHEAST SOUTH CAROLINA...
  NORTHERN HAMPTON COUNTY IN SOUTHEAST SOUTH CAROLINA...

* UNTIL 1245 AM EDT

* AT 938 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  VERY HEAVY RAIN OCCURRING ALONG A LINE EXTENDING FROM BARTON TO 6
  MILES SOUTH OF RUFFIN...OR ALONG A LINE EXTENDING FROM ALLENDALE TO
  9 MILES WEST OF WALTERBORO. THE AREA OF HEAVY RAIN WAS MOVING EAST
  AT 5 MPH.

  BETWEEN 2 AND 4 INCHES OF RAIN HAS FALLEN ACROSS MUCH OF THE
  AREA THIS EVENING. AN ADDITIONAL 1 TO 3 INCHES WILL BE POSSIBLE
  THROUGH 1245 AM...WHICH WILL LEAD TO AREAS OF FLASH FLOODING.

* FLASH FLOODING IS EXPECTED IN AND AROUND...
  ALLENDALE...HAMPTON...ULMER...CROCKETVILLE...ASHTON...
  WILLIAMS...BELLS CROSSROADS...ISLANDTON...

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 3311 8137 3312 8119 3303 8108 3310 8095
      3310 8093 3307 8090 3309 8089 3313 8090
      3318 8080 3316 8072 3283 8086 3287 8144

$$
4 follow-up statements
339 
WGUS72 KCHS 300212
FFSCHS

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE CHARLESTON SC
1012 PM EDT WED AUG 29 2012

SCC005-029-049-300445-
/O.CON.KCHS.FF.W.0011.000000T0000Z-120830T0445Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
ALLENDALE SC-HAMPTON SC-COLLETON SC-
1012 PM EDT WED AUG 29 2012

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1245 AM EDT FOR
NORTHWESTERN COLLETON...NORTHERN HAMPTON AND EASTERN ALLENDALE
COUNTIES...

AT 1012 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED 
TO INDICATE AN AREA OF HEAVY RAIN CAPABLE OF PRODUCING FLASH FLOODING. 
THESE STORMS WERE LOCATED ALONG A LINE FROM ALLENDALE TO 13 MILES 
WEST OF WALTERBORO...MOVING EAST AT 5 MPH. RADAR ESTIMATES BETWEEN
2 AND 5 INCHES OF RAIN HAS FALLEN ACROSS MUCH OF THE WARNED
AREA THIS EVENING. AN ADDITIONAL 1 TO 2 INCHES IS POSSIBLE THROUGH 
1245 AM WHICH WILL RESULT IN AREAS OF FLASH FLOODING.

AT 1005 PM EDT...THE ALLENDALE COUNTY WARNING POINT REPORTED THAT 
FLOOD WATERS WERE COVERING PARTS OF HIGHWAY 278 NEAR FAIRFAX.
AT LAST REPORT...THE ROAD WAS PASSABLE. IF APPROACHING THIS 
AREA...FOLLOW INSTRUCTIONS BY LAW ENFORCEMENT.

FLASH FLOODING IS EXPECTED IN AND AROUND ALLENDALE...APPLETON...
ASHTON...BARTON...BRUNSON...COLLETON...CROCKETVILLE...FAIRFAX...
GIFFORD...HAMPTON...ISLANDTON...LODGE...MILEY...PADGETTS...RUFFIN...
SEIGLING...SMOAKS...SYCAMORE...ULMER...VARNVILLE AND WILLIAMS.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

WATER DEPTH IS NEARLY IMPOSSIBLE TO DETERMINE AT NIGHT. DO NOT
ATTEMPT TO CROSS WATER ON THE ROADWAY EVEN IF IT APPEARS SHALLOW.
FIND AN ALTERNATE ROUTE. A SHORT DELAY IN YOUR TRAVEL PLANS IS BETTER
THAN LOSING YOUR CAR...OR YOUR LIFE.

&&

LAT...LON 3311 8137 3312 8119 3303 8108 3310 8095
      3310 8093 3307 8090 3309 8089 3313 8090
      3318 8080 3316 8072 3283 8086 3287 8144

$$
058 
WGUS72 KCHS 300251
FFSCHS

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE CHARLESTON SC
1051 PM EDT WED AUG 29 2012

SCC005-029-049-300445-
/O.CON.KCHS.FF.W.0011.000000T0000Z-120830T0445Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
ALLENDALE SC-HAMPTON SC-COLLETON SC-
1051 PM EDT WED AUG 29 2012

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1245 AM EDT FOR
NORTHWESTERN COLLETON...NORTHERN HAMPTON AND EASTERN ALLENDALE
COUNTIES...

AT 1049 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
MAINLY LIGHT TO MODERATE RAINS FALLING FROM ALLENDALE EAST TO 
ISLANDTON AND EXTENDING SOUTH TO HAMPTON. RAINFALL AMOUNTS OF 2 TO 
5 INCHES HAVE BEEN REPORTED ACROSS MUCH OF THIS AREA THIS EVENING. 
ALTHOUGH ONLY MINOR ADDITIONAL RAINFALL AMOUNTS ARE EXPECTED TROUGH 
1245 AM...THE RISK FOR FLASH FLOODING CONTINUES AS IT WILL TAKE SOME 
TIME FOR FLOOD WATERS TO RECEDE.

AT 1040 PM...THE ALLENDALE COUNTY WARNING POINT INDICATED SEVERAL
ROADWAYS THROUGHOUT THE COUNTY HAVE FLOOD WATERS FLOWING OVER THEM
AND SEVERAL ARE CLOSED DUE TO FLASH FLOODING. MOST OF THE CLOSED 
ROADWAYS ARE NEAR THE CITY OF ALLENDALE. SIMILAR CONDITIONS ARE 
LIKELY OCCURRING OVER NORTHERN HAMPTON COUNTY AND NORTHWEST COLLETON 
COUNTY.

FLASH FLOODING IS EXPECTED IN AND AROUND ALLENDALE...APPLETON...
ASHTON...BARTON...BRUNSON...COLLETON...CROCKETVILLE...FAIRFAX...
GIFFORD...HAMPTON...ISLANDTON...LODGE...MILEY...PADGETTS...RUFFIN...
SEIGLING...SMOAKS...SYCAMORE...ULMER...VARNVILLE AND WILLIAMS.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THE MAJORITY OF FLOOD DEATHS ARE DUE TO PEOPLE DRIVING INTO WATER OF
UNKNOWN DEPTH. JUST ONE FOOT OF FLOWING WATER IS POWERFUL ENOUGH TO
SWEEP VEHICLES OFF THE ROAD. EVEN MODERN SPORT UTILITY VEHICLES ARE
VULNERABLE TO FLOODING. TO AVOID THE RISK OF DEATH...FIND AN
ALTERNATE ROUTE IF THE ROAD IS FLOODED.

EXCESSIVE RUNOFF FROM THESE STORMS WILL CAUSE RAPID FLOODING OF SMALL
CREEKS...ROADWAYS AND LOW-LYING FARMLAND.

&&

LAT...LON 3311 8137 3312 8119 3303 8108 3310 8095
      3310 8093 3307 8090 3309 8089 3313 8090
      3318 8080 3316 8072 3283 8086 3287 8144

$$
121 
WGUS72 KCHS 300347
FFSCHS

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE CHARLESTON SC
1147 PM EDT WED AUG 29 2012

SCC005-029-049-300445-
/O.CON.KCHS.FF.W.0011.000000T0000Z-120830T0445Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
ALLENDALE SC-HAMPTON SC-COLLETON SC-
1147 PM EDT WED AUG 29 2012

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1245 AM EDT FOR
NORTHWESTERN COLLETON...NORTHERN HAMPTON AND EASTERN ALLENDALE
COUNTIES...

AT 1147 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
MAINLY LIGHT FALLING FROM ALLENDALE EAST TO ISLANDTON AND EXTENDING 
SOUTH TO HAMPTON. RAINFALL AMOUNTS OF 2 TO 6 INCHES HAVE BEEN 
REPORTED ACROSS MUCH OF THIS AREA THIS EVENING. ALTHOUGH THE RAIN
IS ENDING...IT WILL TAKE TIME FOR FLOOD WATERS TO RECEDE.

AT 1140 PM...THE ALLENDALE COUNTY WARNING POINT INDICATED SEVERAL 
ROADWAYS THROUGHOUT THE COUNTY CONTINUE TO HAVE FLOOD WATERS 
FLOWING OVER THEM AND SEVERAL REMAIN CLOSED. MOST OF THE CLOSED 
ROADWAYS ARE NEAR THE CITY OF ALLENDALE. SIMILAR CONDITIONS MAY BE 
ONGOING ACROSS PARTS OF NORTHERN HAMPTON COUNTY AND NORTHWEST 
COLLETON COUNTY.

FLASH FLOODING IS EXPECTED IN AND AROUND... 
ALLENDALE...APPLETON...ASHTON...BARTON...BRUNSON...COLLETON. ..
CROCKETVILLE...FAIRFAX...GIFFORD...HAMPTON...ISLANDTON...
LODGE...MILEY...PADGETTS...RUFFIN...SEIGLING...SMOAKS...
SYCAMORE...ULMER...VARNVILLE AND WILLIAMS.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THE MAJORITY OF FLOOD DEATHS ARE DUE TO PEOPLE DRIVING INTO WATER OF
UNKNOWN DEPTH. JUST ONE FOOT OF FLOWING WATER IS POWERFUL ENOUGH TO
SWEEP VEHICLES OFF THE ROAD. EVEN MODERN SPORT UTILITY VEHICLES ARE
VULNERABLE TO FLOODING. TO AVOID THE RISK OF DEATH...FIND AN
ALTERNATE ROUTE IF THE ROAD IS FLOODED.

&&

LAT...LON 3311 8137 3312 8119 3303 8108 3310 8095
      3310 8093 3307 8090 3309 8089 3313 8090
      3318 8080 3316 8072 3283 8086 3287 8144

$$
479 
WGUS72 KCHS 300438
FFSCHS

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE CHARLESTON SC
1238 AM EDT THU AUG 30 2012

SCC005-029-049-300447-
/O.EXP.KCHS.FF.W.0011.000000T0000Z-120830T0445Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
ALLENDALE SC-HAMPTON SC-COLLETON SC-
1238 AM EDT THU AUG 30 2012

...THE FLASH FLOOD WARNING WILL EXPIRE AT 1245 AM EDT FOR FOR
NORTHWESTERN COLLETON...NORTHERN HAMPTON AND EASTERN ALLENDALE
COUNTIES...

HEAVY RAIN AND THE THREAT FOR FLASH FLOODING HAVE ENDED. THE FLASH 
FLOOD WARNING WILL THEREFORE BE ALLOWED TO EXPIRE. 

ALTHOUGH HEAVY RAIN AND 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. 

LAT...LON 3311 8137 3312 8119 3303 8108 3310 8095
      3310 8093 3307 8090 3309 8089 3313 8090
      3318 8080 3316 8072 3283 8086 3287 8144

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 29, 8:34 PM EDTAreal Flood AdvisoryCHSAllendale, Colleton, Hampton86 min
Aug 29, 11:06 PM EDTAreal Flood AdvisoryCHSCharleston, Colleton, Dorchester48 min

Nearby

Flash Flood Warnings in South Carolina, 2012Every 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.