Alert archive / South Carolina / Flash Flood Watches in 2020

Flash Flood Watch 4, NWS Columbia, SC

May 19, 20209 counties in South Carolina

NWS Columbia, SC issued this flash flood watch at May 19, 2020, 3:39 AM EDT for 9 counties in South Carolina. It was in force for 52 hr.

The area

The counties it named.

The facts

Issued
May 19, 2020, 3:39 AM EDT (07:39 UTC)
Expired
May 21, 2020, 8:00 AM EDT
In force
52 hr
Issued by
NWS Columbia, SC
Flood severity
None

Counties Chesterfield County, SC, Fairfield County, SC, Kershaw County, SC, Lancaster County, SC, Lee County, SC, Lexington County, SC, Newberry County, SC, Richland County, SC, Sumter County, SC

The nearest sounding before it

Greensboro/Hi Pt, NC (KGSO), launched 00:00Z, 7.7 hours before the alert went out and 217 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 2020-05-19Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 19 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 2020-05-19The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 60 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
19 J/kg
Mixed-layer CIN
-60 J/kg
Mixed-layer LCL
554 m above ground
0-6 km bulk shear
28 kt
0-1 km storm-relative helicity
60 m²/s²
0-3 km storm-relative helicity
103 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The office that day

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

IssuedProductOfficeCountiesLasted
May 18, 8:43 PM EDTSpecial Weather StatementCAESaluda47 min
May 18, 9:42 PM EDTSpecial Weather StatementCAELexington33 min
May 19, 12:28 AM EDTAreal Flood AdvisoryCAELexington, Richland4 hr
May 19, 12:38 AM EDTSpecial Weather StatementCAEKershaw52 min
May 19, 1:11 AM EDTSpecial Weather StatementCAELancaster49 min
May 19, 1:38 PM EDTSpecial Weather StatementCAEFairfield37 min
May 19, 2:30 PM EDTRiver Flood WarningCAECalhoun, Lexington, Richland21 days
May 19, 2:30 PM EDTRiver Flood WarningCAECalhoun, Richland13 days
May 19, 2:34 PM EDTRiver Flood AdvisoryCAELexington, Richland16 hr
May 19, 2:39 PM EDTRiver Flood WarningCAEChesterfield, Marlboro7 days
May 19, 2:44 PM EDTSpecial Weather StatementCAESaluda31 min
May 19, 3:47 PM EDTRiver Flood WarningCAEGreenwood, Newberry, Saluda4 days

Nearby

Flash Flood Watches in South Carolina, 2020Every flash flood watch in 2020

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.