Alert archive / South Carolina / Flash Flood Warnings in 2012

Flash Flood Warning 1, NWS Charleston, SC

May 16, 2012Berkeley County, South Carolina

NWS Charleston, SC issued this flash flood warning at May 16, 2012, 8:27 PM EDT for Berkeley County, South 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: May 16, 2012, 8:27 PM EDT (00:27 UTC)
Expired: May 16, 2012, 10:30 PM EDT
In force: 2 hr
Issued by: NWS Charleston, SC
Area: Storm-based polygon
Flood severity: None

County Berkeley County, SC

The radar

The Wilmington radar (KLTX), 142 km from the middle of the area, began a volume at 00:30 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
May 16, 9:13 PM EDT	FLOOD	1 E Jamestown, SC	LOCAL FIRE DEPT EMPLOYEE REPORTED HIS AND NEIGHBORS YARD HAS FLOODED AND IS 2 TO 3 INCHES UNDER WATER.
May 16, 9:57 PM EDT	HEAVY RAIN 7	Jamestown, SC	JAMESTOWN FIRE DEPARTMENT REPORTED AT LEAST 7 INCHES OF RAIN HAS FALLEN SINCE 7PM.

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, 0.5 hours before the alert went out and 49 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: 1393 J/kg
Mixed-layer CIN: -27 J/kg
Mixed-layer LCL: 1014 m above ground
0-6 km bulk shear: 19 kt
0-1 km storm-relative helicity: 2 m²/s²
0-3 km storm-relative helicity: 37 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.1

Open this sounding in Storm Lab

The text

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

260 
WGUS52 KCHS 170027
FFWCHS
SCC015-170230-
/O.NEW.KCHS.FF.W.0001.120517T0027Z-120517T0230Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE CHARLESTON SC
827 PM EDT WED MAY 16 2012

THE NATIONAL WEATHER SERVICE IN CHARLESTON HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  EAST CENTRAL BERKELEY COUNTY IN SOUTHEAST SOUTH CAROLINA...

* UNTIL 1030 PM EDT

* AT 826 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  VERY HEAVY RAIN OCCURRING NEAR JAMESTOWN...OR ABOUT 18 MILES
  NORTHWEST OF MCCLELLANVILLE. THE AREA OF HEAVY RAIN WAS NEARLY
  STATIONARY.
 
  UP TO 3 INCHES OF RAIN HAS FALLEN IN THE AREA SINCE 7 PM.
  AN ADDITIONAL 1 TO 3 INCHES OF RAIN CAN BE EXPECTED THROUGH
  1030 PM AS ADDITIONAL HEAVY RAIN FALLS. THIS MAY RESULT
  IN AREAS OF FLASH FLOODING.

* FLASH FLOODING IS EXPECTED IN AND AROUND...
  JAMESTOWN...

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 3317 7968 3324 7983 3333 7973 3327 7956
      3326 7954

$$

4 follow-up statements

205 
WGUS72 KCHS 170105
FFSCHS

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE CHARLESTON SC
905 PM EDT WED MAY 16 2012

SCC015-170230-
/O.CON.KCHS.FF.W.0001.000000T0000Z-120517T0230Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BERKELEY SC-
905 PM EDT WED MAY 16 2012

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1030 PM EDT FOR EAST
CENTRAL BERKELEY COUNTY...

AT 904 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO 
INDICATE THUNDERSTORMS WITH EXTREMELY HEAVY RAIN OCCURRING OVER 
JAMESTOWN. BETWEEN 3 AND 5 INCHES OF RAIN HAS FALLEN OVER THIS AREA 
SINCE 7 PM AND WITH HEAVY RAIN EXPECTED TO PERSIST THROUGH AT LEAST 
THE NEXT HOUR...AN ADDITIONAL 2 TO 3 INCHES COULD FALL. FLOODING IS 
LIKELY OCCURRING AROUND THE JAMESTOWN AREA AND THE RISK FOR FLOODING 
WILL LIKELY INCREASE AS HIGH TIDE MOVES UP THE LOWER SANTEE RIVER.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

IF YOU CAN NOT SEE THE ROAD DUE TO INTENSE NIGHT RAINFALL...YOU 
SHOULD NOT DRIVE. EXCESSIVE RUNOFF FROM THESE STORMS WILL CAUSE 
RAPID FLOODING OF SMALL CREEKS...ROADWAYS AND LOW-LYING FARMLAND.

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

&&

LAT...LON 3317 7968 3324 7983 3333 7973 3327 7956
      3326 7954

$$

054 
WGUS72 KCHS 170116
FFSCHS

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE CHARLESTON SC
916 PM EDT WED MAY 16 2012

SCC015-170230-
/O.CON.KCHS.FF.W.0001.000000T0000Z-120517T0230Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BERKELEY SC-
916 PM EDT WED MAY 16 2012

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1030 PM EDT FOR EAST
CENTRAL BERKELEY COUNTY...

AT 915 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO 
INDICATE THUNDERSTORMS WITH EXTREMELY HEAVY RAIN OCCURRING OVER 
JAMESTOWN. BETWEEN 3 AND 5 INCHES OF RAIN HAS FALLEN OVER THIS AREA 
SINCE 7 PM AND WITH HEAVY RAIN EXPECTED TO PERSIST THROUGH AT LEAST 
THE NEXT HOUR...AN ADDITIONAL 2 TO 3 INCHES COULD FALL. FLOODING IS 
LIKELY OCCURRING AROUND THE JAMESTOWN AREA AND THE RISK FOR FLOODING 
WILL LIKELY INCREASE AS HIGH TIDE MOVES UP THE LOWER SANTEE RIVER.

AT 913 PM EDT...SPOTTERS REPORTED EXTENSIVE FLOODING OF YARDS EAST 
OF JAMESTOWN.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

IF YOU CAN NOT SEE THE ROAD DUE TO INTENSE NIGHT RAINFALL...YOU 
SHOULD NOT DRIVE. EXCESSIVE RUNOFF FROM THESE STORMS WILL CAUSE 
RAPID FLOODING OF SMALL CREEKS...ROADWAYS AND LOW-LYING FARMLAND.

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 3317 7968 3324 7983 3333 7973 3327 7956
      3326 7954

$$

385 
WGUS72 KCHS 170144
FFSCHS

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE CHARLESTON SC
944 PM EDT WED MAY 16 2012

SCC015-170230-
/O.CON.KCHS.FF.W.0001.000000T0000Z-120517T0230Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BERKELEY SC-
944 PM EDT WED MAY 16 2012

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1030 PM EDT FOR EAST
CENTRAL BERKELEY COUNTY...

AT 944 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
THE MOST INTENSE RAINFALL IS DRIFTING WEST OUT OF THE JAMESTOWN
AREA. ALTHOUGH ADDITIONAL RAINFALL AMOUNTS WILL BE LIGHT...IT 
WILL TAKE SOME TIME FOR FLOOD WATERS TO RECEDE. RADAR ESTIMATES
AS MUCH AS 4 TO 6 INCHES OF RAIN HAS FALLEN AROUND JAMESTOWN
SINCE 7 PM.

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 3317 7968 3324 7983 3333 7973 3327 7956
      3326 7954

$$

691 
WGUS72 KCHS 170227
FFSCHS

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE CHARLESTON SC
1027 PM EDT WED MAY 16 2012

SCC015-170235-
/O.EXP.KCHS.FF.W.0001.000000T0000Z-120517T0230Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BERKELEY SC-
1027 PM EDT WED MAY 16 2012

...THE FLASH FLOOD WARNING WILL EXPIRE AT 1030 PM EDT FOR FOR EAST
CENTRAL BERKELEY COUNTY...

RAINS HAVE ENDED ACROSS THE JAMESTOWN AREA AND THE RISK FOR 
ADDITIONAL NEAR TERM FLOODING HAS ENDED. ADDITIONAL SHOWERS AND
THUNDERSTORMS COULD OCCUR OVERNIGHT.

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 3317 7968 3324 7983 3333 7973 3327 7956
      3326 7954

$$

The office that day

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

Issued	Product	Office	Counties	Lasted
May 16, 8:03 PM EDT	Areal Flood Advisory	CHS	Berkeley	42 min
May 16, 9:20 PM EDT	Areal Flood Advisory	CHS	Charleston	2 hr
May 17, 1:25 AM EDT	Special Weather Statement	CHS	Charleston	50 min
May 17, 2:11 AM EDT	Areal Flood Advisory	CHS	Berkeley, Charleston	3 hr
May 17, 3:19 AM EDT	Special Weather Statement	CHS	Charleston	26 min
May 17, 4:35 AM EDT	Areal Flood Advisory	CHS	Charleston	115 min
May 17, 12:53 PM EDT	Special Weather Statement	CHS	Berkeley	37 min
May 17, 1:12 PM EDT	Areal Flood Advisory	CHS	Berkeley, Dorchester	93 min
May 17, 1:25 PM EDT	Special Weather Statement	CHS	Dorchester	65 min
May 17, 1:29 PM EDT	Special Weather Statement	CHS	Hampton	61 min
May 17, 2:12 PM EDT	Areal Flood Advisory	CHS	Berkeley, Charleston, Colleton, Dorchester	93 min
May 17, 2:32 PM EDT	Special Weather Statement	CHS	Colleton, Hampton	58 min
May 17, 2:49 PM EDT	Special Weather Statement	CHS	Jasper	56 min
May 17, 3:04 PM EDT	Severe Thunderstorm Warning	CHS	Charleston, Colleton	17 min
May 17, 4:45 PM EDT	Areal Flood Advisory	CHS	Jasper	60 min

Nearby

Flash Flood Warnings in South Carolina, 2012 Every 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.