Alert archive / South Carolina / Flash Flood Warnings in 2012

Flash Flood Warning 4, NWS Charleston, SC

May 29, 20125 counties in South Carolina

NWS Charleston, SC issued this flash flood warning at May 29, 2012, 11:51 PM EDT for 5 counties in South Carolina. It was in force for 3 hr. 1 report 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
May 29, 2012, 11:51 PM EDT (03:51 UTC)
Expired
May 30, 2012, 3:18 AM EDT
In force
3 hr
Issued by
NWS Charleston, SC
Area
Storm-based polygon
Flood severity
None

Counties Beaufort County, SC, Berkeley County, SC, Charleston County, SC, Colleton County, SC, Dorchester County, SC

The radar

The Charleston,SC radar (KCLX), 92 km from the middle of the area, began a volume at 03:51 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
May 30, 12:31 AM EDTFLASH FLOODCharleston, SCASHLEY AVENUE BETWEEN SUMTER STREET AND RACE STREET FLOODED AND IMPASSABLE.

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

The nearest sounding before it

Charleston AFB, SC (KCHS), launched 00:00Z, 3.9 hours before the alert went out and 10 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, Charleston AFB, SC at 00:00Z on 2012-05-30Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 907 joules per kilogram.LCLEL10008507005003002001001 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, Charleston AFB, SC at 00:00Z on 2012-05-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 99 square meters per square second.193958Sfc1 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
907 J/kg
Mixed-layer CIN
0 J/kg
Mixed-layer LCL
540 m above ground
0-6 km bulk shear
18 kt
0-1 km storm-relative helicity
99 m²/s²
0-3 km storm-relative helicity
121 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.

634 
WGUS52 KCHS 300351
FFWCHS
SCC013-015-019-029-035-300745-
/O.NEW.KCHS.FF.W.0004.120530T0351Z-120530T0745Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE CHARLESTON SC
1151 PM EDT TUE MAY 29 2012

THE NATIONAL WEATHER SERVICE IN CHARLESTON HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  NORTHEASTERN BEAUFORT COUNTY IN SOUTHEAST SOUTH CAROLINA...
  BERKELEY COUNTY IN SOUTHEAST SOUTH CAROLINA...
  CHARLESTON COUNTY IN SOUTHEAST SOUTH CAROLINA...
  EASTERN COLLETON COUNTY IN SOUTHEAST SOUTH CAROLINA...
  DORCHESTER COUNTY IN SOUTHEAST SOUTH CAROLINA...

* UNTIL 345 AM EDT

* AT 1147 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  VERY HEAVY RAIN OCCURRING ALONG A LINE EXTENDING FROM BENNETTS
  POINT TO 26 MILES SOUTHEAST OF FRIPP ISLAND...OR ALONG A LINE
  EXTENDING FROM 11 MILES WEST OF EDISTO BEACH TO 32 MILES SOUTH OF
  EDISTO BEACH...MOVING NORTHEAST AT 15 MPH.

  TORRENTIAL RAINS ASSOCIATED WITH TROPICAL DEPRESSION BERYL WERE
  EXPANDING OVER THE AREA AND WILL CONTINUE INTO THE OVERNIGHT 
  HOURS. BOTH RURAL AND URBAN FLASH FLOODING WILL LIKELY OCCUR WITH 
  SOME RAINFALL AMOUNTS FROM 3 TO 5 INCHES LOCALLY WITHIN THE 
  WARNING AREA. 

* FLASH FLOODING IS EXPECTED IN AND AROUND...
  FRIPP ISLAND...LADYS ISLAND...BENNETTS POINT...WHITE HALL...GREEN
  POND...HENDERSONVILLE...ASHEPOO...CHARLESTON...MOUNT PLEASANT...
  SUMMERVILLE...MONCKS CORNER...JACKSONBORO...DOWNTOWN CHARLESTON.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

HIGH TIDE OVERNIGHT WILL INHIBIT RUNOFF OF HEAVY RAIN...FLOODING 
AREAS OF POOR DRAINAGE IN DOWNTOWN CHARLESTON. AREAS MOST PRONE TO 
FLOODING INCLUDE THE MARKET...CROSSTOWN...EAST BAY STREET AND 
MORRISON DRIVE.

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

&&

LAT...LON 3300 7936 3301 7957 3290 7957 3275 7986
      3260 7999 3255 8020 3243 8035 3249 8036
      3248 8047 3231 8044 3242 8071 3268 8082
      3327 8063 3333 8052 3326 8043 3327 8030
      3345 8022 3351 7999 3332 7974 3314 7926

$$
3 follow-up statements
677 
WGUS72 KCHS 300520
FFSCHS

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE CHARLESTON SC
120 AM EDT WED MAY 30 2012

SCC013-300523-
/O.CAN.KCHS.FF.W.0004.000000T0000Z-120530T0745Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BEAUFORT SC-
120 AM EDT WED MAY 30 2012

...THE FLASH FLOOD WARNING HAS BEEN CANCELLED FOR NORTHEASTERN
BEAUFORT COUNTY...

LAT...LON 3300 7936 3301 7957 3290 7957 3275 7986
      3260 7999 3255 8020 3243 8035 3249 8036
      3248 8047 3253 8051 3261 8057 3276 8079
      3327 8063 3333 8052 3326 8043 3327 8030
      3345 8022 3351 7999 3332 7974 3314 7926

$$

SCC015-019-029-035-300745-
/O.CON.KCHS.FF.W.0004.000000T0000Z-120530T0745Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
DORCHESTER SC-CHARLESTON SC-BERKELEY SC-COLLETON SC-
120 AM EDT WED MAY 30 2012

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 345 AM EDT FOR
EASTERN COLLETON...BERKELEY...CHARLESTON AND DORCHESTER COUNTIES...

AT 115 AM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE AREAS OF HEAVY RAIN CAPABLE OF PRODUCING FLASH FLOODING. 
THESE RAINS WERE LOCATED ALONG A LINE EXTENDING FROM 15 MILES 
SOUTHEAST OF BULL ISLAND TO AWENDAW TO 7 MILES SOUTHWEST OF 
CROSS...OR ALONG A LINE EXTENDING FROM 23 MILES EAST OF MOUNT 
PLEASANT TO 13 MILES WEST OF MCCLELLANVILLE TO 11 MILES WEST OF 
MONCKS CORNER...MOVING NORTH AT 30 MPH. 

FLASH FLOODING IS EXPECTED IN AND AROUND BULL ISLAND... CAINHOY... 
CAPE ISLAND...CAPE ROMAIN...CAPERS INLET...CHARLES TOWNE 
LANDING...DOWNTOWN CHARLESTON...EADYTOWN...EASTERN LAKE 
MARION...EDISTO ISLAND...FORT JOHNSON...GARRIS LANDING... 
HARLEYVILLE...HUGER...JAMES ISLAND...JAMESTOWN...SAINT GEORGE... 
SAINT STEPHEN...SANGAREE...SANTEE COASTAL RESERVE...SUMMERVILLE.

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.

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 3300 7936 3301 7957 3290 7957 3275 7986
      3260 7999 3255 8020 3243 8035 3249 8036
      3248 8047 3253 8051 3261 8057 3276 8079
      3327 8063 3333 8052 3326 8043 3327 8030
      3345 8022 3351 7999 3332 7974 3314 7926

$$
554 
WGUS72 KCHS 300616
FFSCHS

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE CHARLESTON SC
216 AM EDT WED MAY 30 2012

SCC029-300621-
/O.CAN.KCHS.FF.W.0004.000000T0000Z-120530T0745Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
COLLETON SC-
216 AM EDT WED MAY 30 2012

...THE FLASH FLOOD WARNING HAS BEEN CANCELLED FOR EASTERN COLLETON
COUNTY...

LAT...LON 3300 7936 3301 7957 3290 7957 3275 7986
      3269 7991 3279 8001 3285 8007 3290 8017
      3300 8030 3310 8044 3333 8052 3326 8043
      3327 8030 3345 8022 3351 7999 3332 7974
      3314 7926

$$

SCC015-019-035-300745-
/O.CON.KCHS.FF.W.0004.000000T0000Z-120530T0745Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
DORCHESTER SC-CHARLESTON SC-BERKELEY SC-
216 AM EDT WED MAY 30 2012

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 345 AM EDT FOR
BERKELEY...EASTERN CHARLESTON AND NORTHEASTERN DORCHESTER COUNTIES...

AT 212 AM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE AREA OF HEAVY RAIN CAPABLE OF PRODUCING FLASH FLOODING. 
THESE STORMS WERE LOCATED ALONG A LINE EXTENDING FROM MCCLELLANVILLE
TO JAMESTOWN TO 7 MILES WEST OF CROSS...OR ALONG A LINE EXTENDING
FROM MCCLELLANVILLE TO 19 MILES NORTHEAST OF MONCKS CORNER TO 17
MILES NORTHEAST OF INDIAN FIELD...MOVING NORTH AT 30 MPH.

HEAVY RAINS IN ASSOCIATION WITH TROPICAL DEPRESSION BERYL HAD MOVED
INTO NORTHEAST CHARLESTON COUNTY AND UPPER BERKELEY COUNTY. AN
ADDITIONAL 1 TO 2 INCHES OF RAIN IS POSSIBLE.

FLASH FLOODING IS EXPECTED IN AND AROUND JAMESTOWN...BONNEAU 
BEACH...BULL ISLAND...CAPE ROMAIN...CAPERS INLET...DOWNTOWN 
CHARLESTON...EADYTOWN...HARLEYVILLE...HUGER... JAMESTOWN... 
JEDBURG...AND SAINT STEPHEN.

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 3300 7936 3301 7957 3290 7957 3275 7986
      3269 7991 3279 8001 3285 8007 3290 8017
      3300 8030 3310 8044 3333 8052 3326 8043
      3327 8030 3345 8022 3351 7999 3332 7974
      3314 7926

$$
581 
WGUS72 KCHS 300718
FFSCHS

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE CHARLESTON SC
318 AM EDT WED MAY 30 2012

SCC015-019-035-300728-
/O.CAN.KCHS.FF.W.0004.000000T0000Z-120530T0745Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
DORCHESTER SC-CHARLESTON SC-BERKELEY SC-
318 AM EDT WED MAY 30 2012

...THE FLASH FLOOD WARNING HAS BEEN CANCELLED FOR BERKELEY...EASTERN
CHARLESTON AND NORTHEASTERN DORCHESTER COUNTIES...

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 3300 7936 3301 7957 3290 7957 3275 7986
      3269 7991 3279 8001 3285 8007 3290 8017
      3300 8030 3310 8044 3333 8052 3326 8043
      3327 8030 3345 8022 3351 7999 3332 7974
      3314 7926

$$

The office that day

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

IssuedProductOfficeCountiesLasted
May 29, 9:00 PM EDTAreal Flood AdvisoryCHSBerkeley, Dorchester3 hr
May 29, 9:08 PM EDTAreal Flood AdvisoryCHSAllendale112 min
May 29, 9:59 PM EDTAreal Flood AdvisoryCHSBeaufort, Hampton, Jasper2 hr
May 29, 10:36 PM EDTFlash Flood WarningCHSBeaufort, Jasper2 hr
May 29, 11:28 PM EDTAreal Flood AdvisoryCHSBerkeley, Charleston, Dorchester3 hr
May 30, 12:05 AM EDTSpecial Weather StatementCHSBerkeley, Charleston85 min
May 30, 6:42 AM EDTLake Wind AdvisoryCHSBerkeley4 hr

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.