Alert archive / South Carolina / Areal Flood Advisories in 2021

Areal Flood Advisory 75, NWS Columbia, SC

August 22, 20215 counties in South Carolina

NWS Columbia, SC issued this areal flood advisory at Aug 22, 2021, 4:55 PM EDT for 5 counties in South Carolina. It was in force for 103 min.

The area

The counties it named.

The facts

Issued: Aug 22, 2021, 4:55 PM EDT (20:55 UTC)
Expired: Aug 22, 2021, 6:38 PM EDT
In force: 103 min
Issued by: NWS Columbia, SC
Area: Storm-based polygon

Counties Bamberg County, SC, Barnwell County, SC, Calhoun County, SC, Clarendon County, SC, Orangeburg County, SC

The radar

The Columbia radar (KCAE), 60 km from the middle of the area, began a volume at 20:54 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, 8.9 hours before the alert went out and 101 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: 890 J/kg
Mixed-layer CIN: -34 J/kg
Mixed-layer LCL: 704 m above ground
0-6 km bulk shear: 19 kt
0-1 km storm-relative helicity: 60 m²/s²
0-3 km storm-relative helicity: 92 m²/s²
Significant tornado parameter: 0.1
Supercell composite: 1.1

Open this sounding in Storm Lab

What forecasters said that day

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

NWS Columbia, SC wrote its last area forecast discussion before this areal flood advisory went out at Aug 22, 3:03 PM EDT, 1 hour 52 minutes earlier.

Area forecast discussion, Aug 22, 3:03 PM EDT, 1 hour 52 minutes before

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Hazardous weather outlook, Aug 22, 4:20 AM EDT, 12 hours 35 minutes before

Hazardous Weather Outlook
National Weather Service Columbia SC
420 AM EDT Sun Aug 22 2021

GAZ040-063>065-077-SCZ016-018-020>022-025>031-035-037-038-041-115-
116-135>137-230830-
Lincoln-McDuffie-Columbia-Richmond-Burke-Chesterfield-McCormick-
Newberry-Fairfield-Kershaw-Edgefield-Saluda-Lexington-Richland-Lee-
Aiken-Sumter-Barnwell-Calhoun-Clarendon-Bamberg-Northern Lancaster-
Southern Lancaster-Northwestern Orangeburg-Central Orangeburg-
Southeastern Orangeburg-
420 AM EDT Sun Aug 22 2021

This Hazardous Weather Outlook is for the Midlands of South Carolina
and the Central Savannah River area of Georgia.

.DAY ONE...Today and tonight.

The probability for widespread hazardous weather is low.

.DAYS TWO THROUGH SEVEN...Monday through Saturday.

The probability for widespread hazardous weather is low.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected at this time.

In the hours before

Local storm report, Aug 22, 2:57 PM EDT, 1 hour 58 minutes before

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Local storm report, Aug 22, 3:58 PM EDT, 57 minutes before

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Local storm report, Aug 22, 4:25 PM EDT, 30 minutes before

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The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 22, 1:21 AM EDT	Areal Flood Advisory	CAE	Bamberg, Barnwell, Orangeburg	114 min
Aug 22, 11:10 AM EDT	Areal Flood Advisory	CAE	Calhoun, Lexington, Richland	110 min
Aug 22, 12:40 PM EDT	Areal Flood Advisory	CAE	Richland	2 hr
Aug 22, 1:27 PM EDT	Areal Flood Advisory	CAE	Fairfield, Kershaw	2 hr
Aug 22, 1:32 PM EDT	Areal Flood Advisory	CAE	Lexington, Newberry, Richland	118 min
Aug 22, 1:46 PM EDT	Flash Flood Warning Considerable damage threat	CAE	Lexington	119 min
Aug 22, 2:18 PM EDT	Areal Flood Advisory	CAE	Saluda	117 min
Aug 22, 2:41 PM EDT	Areal Flood Advisory	CAE	Calhoun, Lexington, Orangeburg, Richland	3 hr
Aug 22, 3:39 PM EDT	Flash Flood Warning Considerable damage threat	CAE	Aiken, Calhoun, Lexington, Orangeburg, Richland	111 min

Nearby

Areal Flood Advisories in South Carolina, 2021 Every areal flood advisory in 2021

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.