Alert archive / South Carolina / Dense Fog Advisories in 2021

Dense Fog Advisory 2, NWS Charleston, SC

January 15, 2021Allendale County, Colleton County, Hampton County, South Carolina; Bulloch County, Effingham County, Screven County, Georgia

NWS Charleston, SC issued this dense fog advisory at Jan 15, 2021, 8:35 PM EST for Allendale County, Colleton County, Hampton County, South Carolina; Bulloch County, Effingham County, Screven County, Georgia. It was in force for 3 hr.

The area

The counties it named.

The facts

Issued
Jan 15, 2021, 8:35 PM EST (01:35 UTC)
Expired
Jan 15, 2021, 11:16 PM EST
In force
3 hr
Issued by
NWS Charleston, SC

Counties Bulloch County, GA, Effingham County, GA, Screven County, GA, Allendale County, SC, Colleton County, SC, Hampton County, SC

The radar

The Charleston,SC radar (KCLX), 25 km from the middle of the area, began a volume at 01:38 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 00:00Z, 1.6 hours before the alert went out and 124 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, Charleston AFB, SC at 00:00Z on 2021-01-16Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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, Charleston AFB, SC at 00:00Z on 2021-01-16The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 19 square meters per square second.1939587897117136156Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
816 m above ground
0-6 km bulk shear
100 kt
0-1 km storm-relative helicity
19 m²/s²
0-3 km storm-relative helicity
221 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 Charleston, SC wrote its last area forecast discussion before this dense fog advisory went out at Jan 15, 6:10 PM EST, 2 hours 25 minutes earlier.

Area forecast discussion, Jan 15, 6:10 PM EST, 2 hours 25 minutes before
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Hazardous weather outlook, Jan 15, 5:03 PM EST, 3 hours 32 minutes before
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In the hours before

Special weather statement, Jan 15, 6:50 PM EST, 1 hour 45 minutes before
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Special weather statement, Jan 15, 7:18 PM EST, 1 hour 17 minutes before
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    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
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The office that day

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

IssuedProductOfficeCountiesLasted
Jan 16, 3:39 AM ESTGale WarningCHS14 hr

Nearby

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