Alert archive / South Carolina / Flash Flood Warnings in 2017

Flash Flood Warning 7, NWS Charleston, SC

September 11, 2017Beaufort County, Jasper County, South Carolina

NWS Charleston, SC issued this flash flood warning at Sep 11, 2017, 9:22 AM EDT for Beaufort County, Jasper County, South Carolina. It was in force for 8 hr. 3 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
Sep 11, 2017, 9:22 AM EDT (13:22 UTC)
Expired
Sep 11, 2017, 5:15 PM EDT
In force
8 hr
Issued by
NWS Charleston, SC
Area
Storm-based polygon
Flood severity
None

Counties Beaufort County, SC, Jasper County, SC

The radar

The Charleston,SC radar (KCLX), 38 km from the middle of the area, began a volume at 13:24 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
Sep 11, 10:12 AM EDTHEAVY RAIN 01 E Sun City, SCPHOTO OF WATER MOVING OVER FORDING ISLAND ROAD/278 EXIT RAMP ONTO OKATIE HWY/170.
Sep 11, 3:00 PM EDTCOASTAL FLOOD2 S Ladys Island, SCHARBOR RIVER IS FLOWING OVER US 21 AT COUGAR DRIVE.
Sep 11, 3:15 PM EDTFLASH FLOODOld House, SCJASPER COUNTY EMERGENCY MANAGEMENT REPORTED HOMES FLOODED AND INACCESSIBLE ON CHERRY HILL ROAD NEAR THE INTERSECTION WITH HIGHWAY 462. AT LEAST ONE PERSON IS STRANDED AND IN NEED OF RESCUE.

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 12:00Z, 1.4 hours before the alert went out and 85 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 12:00Z on 2017-09-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Charleston AFB, SC at 12:00Z on 2017-09-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 902 square meters per square second.1939587897Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
547 m above ground
0-6 km bulk shear
62 kt
0-1 km storm-relative helicity
902 m²/s²
0-3 km storm-relative helicity
1081 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

926 
WGUS52 KCHS 111322
FFWCHS
SCC013-053-111715-
/O.NEW.KCHS.FF.W.0007.170911T1322Z-170911T1715Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Charleston SC
922 AM EDT MON SEP 11 2017

The National Weather Service in Charleston has issued a

* Flash Flood Warning for portions of...
  Beaufort County in southeastern South Carolina...
  Jasper County in southeastern South Carolina...

* Until 115 PM EDT

* At 921 AM EDT, Doppler radar indicated torrential rainfall moving 
  onshore across much of the southern South Carolina coast. As much 
  as 2 to 4 inches of rain has already fallen across much of 
  Beaufort and Jasper Counties and heavy rain will continue to move 
  onshore as Hurricane Irma moves north this morning. Heavy rains 
  combined with the incoming high tide will produce an enhanced risk 
  for flooding this morning. 

* Some locations that will experience flooding include...
  Hilton Head Island, Bluffton, Beaufort, Port Royal, Ridgeland,
  Yemassee, Bellinger Hill Area and Clarendon.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.

Report flooding directly to the Charleston National Weather Service
at 1-888-383-2024 or email your reports to nws.charlestonsc@noaa.gov.

&&

LAT...LON 3222 8115 3229 8112 3233 8114 3249 8107
      3270 8082 3267 8077 3267 8068 3265 8068
      3260 8065 3259 8058 3257 8058 3256 8055
      3250 8049 3250 8045 3246 8045 3241 8040
      3230 8041 3225 8057 3212 8072 3206 8084

$$
3 follow-up statements
440 
WGUS72 KCHS 111508
FFSCHS

Flash Flood Statement
National Weather Service Charleston SC
1108 AM EDT MON SEP 11 2017

SCC013-053-111715-
/O.CON.KCHS.FF.W.0007.000000T0000Z-170911T1715Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Beaufort SC-Jasper SC-
1108 AM EDT MON SEP 11 2017

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 115 PM EDT FOR
PORTIONS OF BEAUFORT AND JASPER COUNTIES...

At 1106 AM EDT, Doppler radar continued to indicate heavy rains 
associated with Hurricane Irma moving inland across much of the 
lower South Carolina coast. The risk for flash flooding will 
continue to increase over the next few hours as heavy rains combine 
with the approaching elevated high tide. As much as 3 to 6 inches 
has already fallen across much of Beaufort and Jasper Counties. 

Some locations that will experience flooding include...
Hilton Head Island, Bluffton, Beaufort, Port Royal, Ridgeland,
Yemassee, Bellinger Hill Area and Clarendon.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.

Flooding is likely in low-lying coastal areas where high tide will
inhibit runoff of heavy rain.

&&

LAT...LON 3222 8115 3229 8112 3233 8114 3249 8107
      3270 8082 3267 8077 3267 8068 3265 8068
      3260 8065 3259 8058 3257 8058 3256 8055
      3250 8049 3250 8045 3246 8045 3241 8040
      3230 8041 3225 8057 3212 8072 3206 8084

$$
980 
WGUS52 KCHS 111702
FFWCHS
SCC013-053-112115-
/O.EXT.KCHS.FF.W.0007.000000T0000Z-170911T2115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Charleston SC
102 PM EDT MON SEP 11 2017

The National Weather Service in Charleston has extended the

* Flash Flood Warning for portions of...
  Beaufort County in southeastern South Carolina...
  Jasper County in southeastern South Carolina...

* Until 515 PM EDT

* At 100 PM EDT, Doppler radar indicated bands of heavy rain moving 
  inland associated with Hurricane Irma. Reports of widespread 
  flooding have been received across portions of the warned area. 
  The risk for flooding continues.

* Some locations that will experience flooding include...
  Hilton Head Island, Bluffton, Beaufort, Port Royal, Ridgeland,
  Yemassee, Bellinger Hill Area and Clarendon.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.

Report flooding directly to the Charleston National Weather Service
at 1-888-383-2024 or email your reports to nws.charlestonsc@noaa.gov.

&&

LAT...LON 3222 8115 3229 8112 3233 8114 3249 8107
      3270 8082 3267 8077 3267 8068 3265 8068
      3260 8065 3259 8058 3257 8058 3256 8055
      3250 8049 3250 8045 3246 8045 3241 8040
      3230 8041 3225 8057 3212 8072 3206 8084

$$
778 
WGUS72 KCHS 111949
FFSCHS

Flash Flood Statement
National Weather Service Charleston SC
349 PM EDT MON SEP 11 2017

SCC013-053-112115-
/O.CON.KCHS.FF.W.0007.000000T0000Z-170911T2115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Beaufort SC-Jasper SC-
349 PM EDT MON SEP 11 2017

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 515 PM EDT FOR
PORTIONS OF BEAUFORT AND JASPER COUNTIES...

At 345 PM EDT, Doppler radar continued to indicate heavy rains 
associated with Hurricane Irma moving inland across much of the 
lower South Carolina coast. The risk for flash flooding will 
continue as no drainage will occur due to the ongoing significant 
high tides impacting coastal areas. As much as 4 to 8 inches has 
already fallen across much of Beaufort and Jasper Counties.

At 325 pm, Jasper County Emergency Management reported homes were 
flooded along Cherry Hill road near the intersection of highway 462. 
Water rescues are ongoing in some areas.

Some locations that will experience flooding include...
Hilton Head Island, Bluffton, Beaufort, Port Royal, Ridgeland,
Yemassee, Bellinger Hill Area and Clarendon.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.

Report flooding directly to the Charleston National Weather Service
at 1-888-383-2024 or email your reports to nws.charlestonsc@noaa.gov.

&&

LAT...LON 3222 8115 3229 8112 3233 8114 3249 8107
      3270 8082 3267 8077 3267 8068 3265 8068
      3260 8065 3259 8058 3257 8058 3256 8055
      3250 8049 3250 8045 3246 8045 3241 8040
      3230 8041 3225 8057 3212 8072 3206 8084

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 10, 11:30 PM EDTHurricane WarningCHS9 hr
Sep 11, 3:12 AM EDTSpecial Marine WarningCHS2 hr
Sep 11, 3:12 AM EDTSpecial Marine WarningCHS63 min
Sep 11, 3:49 AM EDTSpecial Marine WarningCHS56 min
Sep 11, 4:19 AM EDTSpecial Marine WarningCHS86 min
Sep 11, 5:18 AM EDTSpecial Marine WarningCHS117 min
Sep 11, 7:01 AM EDTSpecial Marine WarningCHS119 min
Sep 11, 7:41 AM EDTSpecial Marine WarningCHS2 hr
Sep 11, 7:45 AM EDTSpecial Marine WarningCHS2 hr
Sep 11, 8:16 AM EDTFlash Flood WarningCHSJasper8 hr
Sep 11, 8:36 AM EDTAreal Flood AdvisoryCHSBeaufort, Jasper84 min
Sep 11, 9:31 AM EDTAreal Flood AdvisoryCHSAllendale, Hampton, Jasper119 min
Sep 11, 9:41 AM EDTSpecial Marine WarningCHS2 hr
Sep 11, 9:50 AM EDTSpecial Marine WarningCHS115 min
Sep 11, 10:31 AM EDTSpecial Marine WarningCHS119 min
Sep 11, 10:44 AM EDTFlash Flood WarningCHSAllendale, Hampton, Jasper7 hr
Sep 11, 10:45 AM EDTRiver Flood WarningCHSBerkeley, Georgetown, Williamsburg24 hr
Sep 11, 11:24 AM EDTFlash Flood Warning EmergencyCHSBerkeley, Charleston, Colleton, Dorchester15 hr
Sep 11, 11:38 AM EDTSpecial Marine WarningCHS2 hr
Sep 11, 11:44 AM EDTAreal Flood AdvisoryCHSAllendale2 hr
Sep 11, 11:51 AM EDTAreal Flood AdvisoryCHSAllendale, Colleton, Dorchester, Hampton114 min
Sep 11, 12:01 PM EDTTornado WarningCHSBeaufort, Charleston, Colleton29 min
Sep 11, 12:23 PM EDTSpecial Marine WarningCHS2 hr
Sep 11, 12:37 PM EDTTornado WarningCHSCharleston23 min
Sep 11, 12:40 PM EDTSpecial Marine WarningCHS65 min
Sep 11, 12:54 PM EDTFlash Flood WarningCHSAllendale, Colleton, Dorchester, Hampton9 hr
Sep 11, 12:59 PM EDTTornado WarningCHSCharleston, Dorchester31 min
Sep 11, 1:10 PM EDTTornado WarningCHSCharleston, Colleton35 min
Sep 11, 1:49 PM EDTTornado WarningCHSCharleston, Colleton, Dorchester26 min
Sep 11, 1:53 PM EDTTornado WarningCHSCharleston, Dorchester24 min
Sep 11, 2:11 PM EDTSpecial Marine WarningCHS94 min
Sep 11, 2:45 PM EDTTornado WarningCHSBeaufort, Colleton30 min
Sep 11, 2:46 PM EDTTornado WarningCHSBerkeley, Charleston, Dorchester16 min
Sep 11, 3:10 PM EDTFlash Flood WarningCHSBerkeley, Colleton, Dorchester7 hr
Sep 11, 3:58 PM EDTSpecial Marine WarningCHS32 min
Sep 11, 4:43 PM EDTSpecial Marine WarningCHS62 min
Sep 11, 4:48 PM EDTAreal Flood WarningCHSJasper7 hr
Sep 11, 5:16 PM EDTAreal Flood WarningCHSAllendale, Beaufort, Hampton, Jasper7 hr

Nearby

Flash Flood Warnings in South Carolina, 2017Every flash flood warning in 2017

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.