Alert archive / South Carolina / Flash Flood Warnings in 2018

Flash Flood Warning 7, NWS Columbia, SC

August 13, 2018Sumter County, South Carolina

NWS Columbia, SC issued this flash flood warning at Aug 13, 2018, 12:18 AM EDT for Sumter County, South Carolina. It was in force for 117 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Aug 13, 2018, 12:18 AM EDT (04:18 UTC)
Expired
Aug 13, 2018, 2:15 AM EDT
In force
117 min
Issued by
NWS Columbia, SC
Area
Storm-based polygon
Flood severity
None

County Sumter County, SC

The radar

The Columbia radar (KCAE), 68 km from the middle of the area, began a volume at 04:19 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

Greensboro/Hi Pt, NC (KGSO), launched 00:00Z, 4.3 hours before the alert went out and 245 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, Greensboro/Hi Pt, NC at 00:00Z on 2018-08-13Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 392 joules per kilogram.LCLLFCEL10008507005003002001001 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, Greensboro/Hi Pt, NC at 00:00Z on 2018-08-13The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -113 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
392 J/kg
Mixed-layer CIN
-100 J/kg
Mixed-layer LCL
1131 m above ground
0-6 km bulk shear
34 kt
0-1 km storm-relative helicity
-113 m²/s²
0-3 km storm-relative helicity
-73 m²/s²
Significant tornado parameter
-0.1
Supercell composite
-0.7

Open this sounding in Storm Lab

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 12, 8:02 PM EDTSpecial Weather StatementCAEKershaw43 min
Aug 12, 11:10 PM EDTSpecial Weather StatementCAESumter50 min
Aug 12, 11:33 PM EDTAreal Flood AdvisoryCAERichland, Sumter117 min
Aug 12, 11:46 PM EDTSpecial Weather StatementCAECalhoun44 min
Aug 13, 12:03 AM EDTSpecial Weather StatementCAESumter57 min
Aug 13, 12:36 AM EDTSpecial Weather StatementCAEClarendon54 min

Nearby

Flash Flood Warnings in South Carolina, 2018Every flash flood warning in 2018

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.