Alert archive / South Carolina / Dense Fog Advisories in 2021

Dense Fog Advisory 1, NWS Columbia, SC

December 31, 202017 counties in South Carolina; 5 counties in Georgia

NWS Columbia, SC issued this dense fog advisory at Dec 31, 2020, 10:10 PM EST for 17 counties in South Carolina; 5 counties in Georgia. It was in force for 10 hr.

The area

The counties it named.

The facts

Issued: Dec 31, 2020, 10:10 PM EST (03:10 UTC)
Expired: Jan 1, 2021, 8:00 AM EST
In force: 10 hr
Issued by: NWS Columbia, SC

All 22 counties

Burke County, GA, Columbia County, GA, Lincoln County, GA, McDuffie County, GA, Richmond County, GA, Aiken County, SC, Bamberg County, SC, Barnwell County, SC, Calhoun County, SC, Chesterfield County, SC, Clarendon County, SC, Edgefield County, SC, Fairfield County, SC, Kershaw County, SC, Lancaster County, SC, Lee County, SC, Lexington County, SC, McCormick County, SC, Newberry County, SC, Richland County, SC, Saluda County, SC, Sumter County, SC

The radar

The Columbia radar (KCAE), 23 km from the middle of the area, began a volume at 03:12 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

Peachtre/Fal Fld, GA (KFFC), launched 00:00Z, 3.2 hours before the alert went out and 298 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 489 m above ground
0-6 km bulk shear: 43 kt
0-1 km storm-relative helicity: 115 m²/s²
0-3 km storm-relative helicity: 191 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 dense fog 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 dense fog advisory went out at Dec 31, 7:08 PM EST, 3 hours 2 minutes earlier.

Area forecast discussion, Dec 31, 7:08 PM EST, 3 hours 2 minutes before

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Hazardous weather outlook, Dec 31, 2:28 PM EST, 7 hours 42 minutes before

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      <div class="status" id="status">Temporary Notice</div>
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        The site you requested is temporarily down for maintenance or an unexpected outage.
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        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
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The office that day

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

Issued	Product	Office	Counties	Lasted
Jan 1, 3:35 PM EST	Flash Flood Watch	CAE	Aiken, Bamberg, Barnwell, Calhoun, Chesterfield, Clarendon and 11 more	34 hr
Jan 1, 4:24 PM EST	River Flood Warning	CAE	Calhoun, Richland	9 days
Jan 1, 4:24 PM EST	River Flood Warning	CAE	Calhoun, Lexington, Richland	5 days
Jan 1, 4:24 PM EST	River Flood Advisory	CAE	Lexington, Richland	4 days
Jan 1, 4:38 PM EST	Special Weather Statement	CAE	Newberry	52 min
Jan 1, 5:28 PM EST	Tornado Warning	CAE	Edgefield, McCormick	32 min
Jan 1, 6:20 PM EST	Special Weather Statement	CAE	Lexington	40 min
Jan 1, 6:34 PM EST	Areal Flood Advisory	CAE	Aiken, Edgefield, Fairfield, Lexington, McCormick, Newberry and 2 more	3 hr
Jan 1, 6:47 PM EST	Areal Flood Advisory	CAE	Calhoun, Kershaw, Lexington, Richland	3 hr
Jan 1, 4:50 PM EST	Special Weather Statement	CAE	Lincoln	40 min
Jan 1, 4:59 PM EST	Tornado Warning	CAE	Columbia, Lincoln, McDuffie	31 min
Jan 1, 6:45 PM EST	Special Weather Statement	CAE	Richmond	60 min

Nearby

Dense Fog Advisories in South Carolina, 2021 Dense Fog Advisories in Georgia, 2021 Every dense fog 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.