Alert archive / Tennessee / Winter Weather Advisories in 2021

Winter Weather Advisory 5, NWS Morristown, TN

January 31, 202122 counties in Tennessee; 7 counties in Virginia; Cherokee County, North Carolina

NWS Morristown, TN issued this winter weather advisory at Jan 31, 2021, 2:12 PM CST for 22 counties in Tennessee; 7 counties in Virginia; Cherokee County, North Carolina. It took effect at Jan 31, 2021, 11:00 PM CST. It was in force for 37 hr.

The area

The counties it named.

The facts

Issued: Jan 31, 2021, 2:12 PM CST (20:12 UTC)
In effect from: Jan 31, 2021, 11:00 PM CST
Expired: Feb 2, 2021, 12:00 PM CST
In force: 37 hr
Issued by: NWS Morristown, TN

All 30 counties

Cherokee County, NC, Bledsoe County, TN, Blount County, TN, Campbell County, TN, Carter County, TN, Claiborne County, TN, Cocke County, TN, Grainger County, TN, Greene County, TN, Hamblen County, TN, Hancock County, TN, Hawkins County, TN, Jefferson County, TN, Johnson County, TN, Marion County, TN, Monroe County, TN, Morgan County, TN, Polk County, TN, Scott County, TN, Sequatchie County, TN, Sevier County, TN, Sullivan County, TN, Washington County, TN, City of Bristol, VA, City of Norton, VA, Lee County, VA, Russell County, VA, Scott County, VA, Washington County, VA, Wise County, VA

The radar

The Knoxville radar (KMRX), 2 km from the middle of the area, began a volume at 20:13 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

Nashville Metro, TN (KBNA), launched 12:00Z, 8.2 hours before the alert went out and 288 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: 513 m above ground
0-6 km bulk shear: 77 kt
0-1 km storm-relative helicity: 602 m²/s²
0-3 km storm-relative helicity: 585 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 winter weather advisory went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Morristown, TN wrote its last area forecast discussion before this winter weather advisory went out at Jan 31, 11:28 AM CST, 2 hours 44 minutes earlier.

Area forecast discussion, Jan 31, 11:28 AM CST, 2 hours 44 minutes before

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Hazardous weather outlook, Jan 31, 9:51 AM CST, 4 hours 21 minutes before

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In the hours before

Local storm report, Jan 31, 11:35 AM CST, 2 hours 37 minutes before

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Local storm report, Jan 31, 11:54 AM CST, 2 hours 18 minutes before

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  <main class="wrap">
    <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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      <p id="message2">
        Please try again in a few minutes.
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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 Morristown, TN issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jan 31, 3:02 AM CST	Winter Storm Watch	MRX	Blount, Cocke, Greene, Monroe, Sevier, Unicoi	11 hr
Jan 31, 2:12 PM CST	Winter Storm Warning	MRX	Blount, Carter, Cocke, Greene, Johnson, Monroe and 2 more	46 hr

Nearby

Winter Weather Advisories in Tennessee, 2021 Winter Weather Advisories in Virginia, 2021 Winter Weather Advisories in North Carolina, 2021 Every winter weather 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.