Alert archive / South Carolina / Tornado Warnings in 2017

Tornado Warning 18, NWS Wilmington, NC

September 11, 2017Georgetown County, Horry County, South Carolina

NWS Wilmington, NC issued this tornado warning at Sep 11, 2017, 10:18 PM EDT for Georgetown County, Horry County, South Carolina. It was in force for 27 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
Sep 11, 2017, 10:18 PM EDT (02:18 UTC)
Expired
Sep 11, 2017, 10:45 PM EDT
In force
27 min
Issued by
NWS Wilmington, NC
Area
Storm-based polygon
Tornado
Radar indicated
Hail
0.0 in

Counties Georgetown County, SC, Horry County, SC

The radar

The Wilmington radar (KLTX), 75 km from the middle of the area, began a volume at 02:22 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 00:00Z, 2.3 hours before the alert went out and 114 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 2017-09-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 458 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, Charleston AFB, SC at 00:00Z on 2017-09-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 334 square meters per square second.19395878Sfc1 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
458 J/kg
Mixed-layer CIN
-17 J/kg
Mixed-layer LCL
652 m above ground
0-6 km bulk shear
49 kt
0-1 km storm-relative helicity
334 m²/s²
0-3 km storm-relative helicity
383 m²/s²
Significant tornado parameter
0.8
Supercell composite
6.7

Open this sounding in Storm Lab

The text

As transmitted.

572 
WFUS52 KILM 120218
TORILM
SCC043-051-120245-
/O.NEW.KILM.TO.W.0018.170912T0218Z-170912T0245Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Wilmington NC
1018 PM EDT MON SEP 11 2017

The National Weather Service in Wilmington has issued a

* Tornado Warning for...
  Northeastern Georgetown County in northeastern South Carolina...
  South central Horry County in northeastern South Carolina...

* Until 1045 PM EDT
    
* At 1017 PM EDT, a severe thunderstorm capable of producing a
  tornado was located near Murrells Inlet, moving northwest at 30
  mph.

  HAZARD...Tornado. 

  SOURCE...Radar indicated rotation. 

  IMPACT...Expect damage to mobile homes, roofs, and vehicles. 

* Locations impacted include...
  Surfside Beach, Garden City, Murrells Inlet, Burgess, Yauhannah,
  Bucksport and Waccamaw Community Hospital.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

&&

LAT...LON 3360 7924 3373 7910 3360 7897 3356 7901
      3354 7902 3353 7904 3352 7904 3352 7905
TIME...MOT...LOC 0217Z 129DEG 27KT 3354 7900 

TORNADO...RADAR INDICATED
HAIL...0.00IN

$$
Ekster
2 follow-up statements
402 
WWUS52 KILM 120232
SVSILM

Severe Weather Statement
National Weather Service Wilmington NC
1032 PM EDT MON SEP 11 2017

SCC043-051-120245-
/O.CON.KILM.TO.W.0018.000000T0000Z-170912T0245Z/
Georgetown SC-Horry SC-
1032 PM EDT MON SEP 11 2017

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 1045 PM EDT FOR
NORTHEASTERN GEORGETOWN AND SOUTHWESTERN HORRY COUNTIES...
    
At 1032 PM EDT, a severe thunderstorm capable of producing a tornado 
was located over Burgess, or near Garden City, moving northwest at 
30 mph.

HAZARD...Tornado. 

SOURCE...Radar indicated rotation. 

IMPACT...Flying debris will be dangerous to those caught without 
         shelter. Mobile homes will be damaged or destroyed. Damage 
         to roofs, windows, and vehicles will occur.  Tree damage is 
         likely. 

Locations impacted include...
Bucksport.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

&&

LAT...LON 3363 7904 3359 7908 3365 7919 3372 7911
TIME...MOT...LOC 0232Z 131DEG 27KT 3362 7907 

TORNADO...RADAR INDICATED
HAIL...0.00IN

$$
mle
388 
WWUS52 KILM 120241
SVSILM

Severe Weather Statement
National Weather Service Wilmington NC
1041 PM EDT MON SEP 11 2017

SCC043-051-120251-
/O.EXP.KILM.TO.W.0018.000000T0000Z-170912T0245Z/
Georgetown SC-Horry SC-
1041 PM EDT MON SEP 11 2017

...THE TORNADO WARNING FOR NORTHEASTERN GEORGETOWN AND SOUTHWESTERN
HORRY COUNTIES WILL EXPIRE AT 1045 PM EDT...
                
The storm which prompted the warning has weakened below severe
limits, and no longer appears capable of producing a tornado.
Therefore the warning will be allowed to expire.  However gusty winds
and heavy rain are still possible with this thunderstorm.

LAT...LON 3363 7904 3359 7908 3365 7919 3372 7911
TIME...MOT...LOC 0241Z 129DEG 27KT 3366 7913 

$$
ekster

The office that day

Everything else NWS Wilmington, NC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Sep 11, 9:43 PM EDTSpecial Marine WarningILM47 min
Sep 11, 10:03 PM EDTSpecial Marine WarningILM27 min
Sep 11, 10:37 PM EDTSpecial Marine WarningILM38 min
Sep 11, 11:26 PM EDTSevere Thunderstorm WarningILMHorry34 min
Sep 12, 1:16 AM EDTAreal Flood AdvisoryILMHorry119 min
Sep 12, 3:00 AM EDTAreal Flood AdvisoryILMDillon, Horry3 hr
Sep 12, 3:13 AM EDTRiver Flood WarningILMHorry6 days
Sep 12, 4:11 AM EDTSmall Craft AdvisoryILM26 hr
Sep 12, 5:17 AM EDTSpecial Marine WarningILM28 min
Sep 12, 7:09 AM EDTSpecial Marine WarningILM111 min

Nearby

Tornado Warnings in South Carolina, 2017Every tornado warning in 2017Tornadoes 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.