Alert archive / Tennessee / Winter Storm Warnings in 2018

Winter Storm Warning 1, NWS Morristown, TN

March 20, 20188 counties in Tennessee; Wise County, City of Norton, Virginia

NWS Morristown, TN issued this winter storm warning at Mar 20, 2018, 4:20 AM EDT for 8 counties in Tennessee; Wise County, City of Norton, Virginia. It took effect at Mar 20, 2018, 11:00 PM EDT. It was in force for 25 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: Mar 20, 2018, 4:20 AM EDT (08:20 UTC)
In effect from: Mar 20, 2018, 11:00 PM EDT
Expired: Mar 22, 2018, 12:00 AM EDT
In force: 25 hr
Issued by: NWS Morristown, TN

Counties Blount County, TN, Carter County, TN, Cocke County, TN, Greene County, TN, Johnson County, TN, Monroe County, TN, Sevier County, TN, Unicoi County, TN, City of Norton, VA, Wise County, VA

The radar

The Knoxville radar (KMRX), 42 km from the middle of the area, began a volume at 08:21 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

Greensboro/Hi Pt, NC (KGSO), launched 00:00Z, 8.3 hours before the alert went out and 273 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: 6 J/kg
Mixed-layer CIN: -4 J/kg
Mixed-layer LCL: 1232 m above ground
0-6 km bulk shear: 59 kt
0-1 km storm-relative helicity: 80 m²/s²
0-3 km storm-relative helicity: 158 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 storm warning 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 storm warning went out at Mar 20, 3:58 AM EDT, 22 minutes earlier.

Area forecast discussion, Mar 20, 3:58 AM EDT, 22 minutes before

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Hazardous weather outlook, Mar 20, 4:06 AM EDT, 14 minutes before

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The office that day

Everything else NWS Morristown, TN issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Mar 19, 8:37 PM EDT	Special Weather Statement	MRX	Morgan	38 min
Mar 19, 8:47 PM EDT	Severe Thunderstorm Warning	MRX	Marion	43 min
Mar 19, 9:20 PM EDT	Special Weather Statement	MRX	Morgan, Roane	55 min
Mar 19, 9:30 PM EDT	Special Weather Statement	MRX	Hamilton	60 min
Mar 19, 9:59 PM EDT	Special Weather Statement	MRX	Jefferson, Knox, Sevier	61 min
Mar 19, 10:07 PM EDT	Special Weather Statement	MRX	Knox	38 min
Mar 20, 4:13 AM EDT	Dense Fog Advisory	MRX	Bledsoe, Bradley, Hamilton, McMinn, Marion, Meigs and 4 more	6 hr
Mar 20, 5:32 AM EDT	Winter Weather Advisory	MRX	Campbell, Claiborne, Morgan, Scott	42 hr

Nearby

Winter Storm Warnings in Tennessee, 2018 Winter Storm Warnings in Virginia, 2018 Every winter storm warning in 2018

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.