Alert archive / South Carolina / Flash Flood Warnings in 2025

Flash Flood Warning 26, NWS Charleston, SC

August 23, 2025Charleston County, South Carolina

NWS Charleston, SC issued this flash flood warning at Aug 23, 2025, 8:26 AM EDT for Charleston County, South Carolina. It was in force for 4 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: Aug 23, 2025, 8:26 AM EDT (12:26 UTC)
Expired: Aug 23, 2025, 12:15 PM EDT
In force: 4 hr
Issued by: NWS Charleston, SC
Area: Storm-based polygon
Damage threat: Considerable
Flood severity: None

County Charleston County, SC

The radar

The Charleston,SC radar (KCLX), 103 km from the middle of the area, began a volume at 12:26 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, 0.4 hours before the alert went out and 18 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: 324 J/kg
Mixed-layer CIN: -2 J/kg
Mixed-layer LCL: 531 m above ground
0-6 km bulk shear: 8 kt
0-1 km storm-relative helicity: -21 m²/s²
0-3 km storm-relative helicity: 23 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

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 Charleston, SC wrote its last area forecast discussion before this flash flood warning went out at Aug 23, 7:41 AM EDT, 45 minutes earlier.

Area forecast discussion, Aug 23, 7:41 AM EDT, 45 minutes before

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Hazardous weather outlook, Aug 23, 7:31 AM EDT, 55 minutes before

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In the hours before

Local storm report, Aug 23, 6:27 AM EDT, 1 hour 59 minutes before

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The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 23, 10:15 AM EDT	Areal Flood Advisory	CHS	Liberty, McIntosh	96 min
Aug 23, 11:02 AM EDT	Coastal Flood Advisory	CHS		13 hr
Aug 23, 11:50 AM EDT	Areal Flood Advisory	CHS	Bryan, Chatham	3 hr
Aug 23, 12:34 PM EDT	Areal Flood Advisory	CHS	Chatham	3 hr
Aug 23, 1:06 PM EDT	Areal Flood Advisory	CHS	Bryan, Chatham	55 min
Aug 23, 2:01 PM EDT	Flash Flood Warning	CHS	Bryan, Chatham	3 hr
Aug 23, 3:19 PM EDT	Areal Flood Warning	CHS	Chatham	3 hr
Aug 22, 9:53 PM EDT	Areal Flood Warning	CHS	Charleston	112 min
Aug 23, 3:39 AM EDT	Coastal Flood Advisory	CHS		7 hr
Aug 23, 7:13 AM EDT	Flash Flood Warning	CHS	Charleston	5 hr
Aug 23, 8:20 AM EDT	Areal Flood Advisory	CHS	Berkeley, Charleston	115 min
Aug 23, 8:58 AM EDT	Areal Flood Warning	CHS	Jasper	13 hr
Aug 23, 10:12 AM EDT	Areal Flood Advisory	CHS	Beaufort, Charleston, Colleton	2 hr
Aug 23, 11:07 AM EDT	Flash Flood Warning	CHS	Berkeley	10 hr
Aug 23, 11:58 AM EDT	Areal Flood Advisory	CHS	Beaufort	3 hr
Aug 23, 12:07 PM EDT	Areal Flood Warning	CHS	Charleston	3 hr
Aug 23, 1:38 PM EDT	Coastal Flood Warning	CHS		10 hr
Aug 23, 3:09 PM EDT	Areal Flood Warning	CHS	Charleston	8 hr

Nearby

Flash Flood Warnings in South Carolina, 2025 Every flash flood warning in 2025

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.