Alert archive / South Carolina / Flash Flood Warnings in 2017

Flash Flood Warning 1, NWS Wilmington, NC

April 23, 2017Georgetown County, Williamsburg County, South Carolina

NWS Wilmington, NC issued this flash flood warning at Apr 23, 2017, 2:12 PM EDT for Georgetown County, Williamsburg County, South Carolina. It was in force for 2 hr. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Apr 23, 2017, 2:12 PM EDT (18:12 UTC)
Expired: Apr 23, 2017, 4:15 PM EDT
In force: 2 hr
Issued by: NWS Wilmington, NC
Area: Storm-based polygon
Flood severity: None

Counties Georgetown County, SC, Williamsburg County, SC

The radar

The Wilmington radar (KLTX), 113 km from the middle of the area, began a volume at 18:14 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 12:00Z, 6.2 hours before the alert went out and 82 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: 373 J/kg
Mixed-layer CIN: -44 J/kg
Mixed-layer LCL: 922 m above ground
0-6 km bulk shear: 26 kt
0-1 km storm-relative helicity: 94 m²/s²
0-3 km storm-relative helicity: 99 m²/s²
Significant tornado parameter: 0.1
Supercell composite: 1.8

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this flash flood warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Wilmington, NC wrote its last area forecast discussion before this flash flood warning went out at Apr 23, 2:04 PM EDT, 8 minutes earlier.

Area forecast discussion, Apr 23, 2:04 PM EDT, 8 minutes before

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Hazardous weather outlook, Apr 23, 4:21 AM EDT, 9 hours 51 minutes before

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The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 23, 3:50 AM EDT	Small Craft Advisory	ILM		61 hr
Apr 23, 4:02 AM EDT	Flash Flood Watch	ILM	Darlington, Dillon, Florence, Georgetown, Horry, Marion and 2 more	48 hr
Apr 23, 1:37 PM EDT	Areal Flood Advisory	ILM	Williamsburg	53 min
Apr 23, 2:32 PM EDT	Special Weather Statement	ILM	Georgetown	28 min
Apr 23, 5:35 AM EDT	Areal Flood Advisory	ILM	Brunswick, New Hanover	3 hr
Apr 23, 9:17 AM EDT	Areal Flood Advisory	ILM	Brunswick, New Hanover	58 min

Nearby

Flash Flood Warnings in South Carolina, 2017 Every 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.