Alert archive / Tennessee / Mesoscale Discussions in 2012

Mesoscale Discussion 58

January 23, 201220 counties in Tennessee

The Storm Prediction Center issued this mesoscale discussion at Jan 23, 2012, 5:28 AM EST for 20 counties in Tennessee. It was in force for 62 min.

The area

The outline as issued.

The facts

Issued: Jan 23, 2012, 5:28 AM EST (10:28 UTC)
Expired: Jan 23, 2012, 6:30 AM EST
In force: 62 min
Issued by: the Storm Prediction Center

Counties Anderson County, TN, Blount County, TN, Bradley County, TN, Campbell County, TN, Claiborne County, TN, Grainger County, TN, Hamblen County, TN, Hamilton County, TN, Hancock County, TN, Hawkins County, TN, Jefferson County, TN, Knox County, TN, Loudon County, TN, McMinn County, TN, Meigs County, TN, Monroe County, TN, Polk County, TN, Roane County, TN, Sevier County, TN, Union County, TN

The radar

The Knoxville radar (KMRX), 93 km from the middle of the area, began a volume at 10:27 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 00:00Z, 10.5 hours before the alert went out and 219 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: 517 m above ground
0-6 km bulk shear: 33 kt
0-1 km storm-relative helicity: 337 m²/s²
0-3 km storm-relative helicity: 371 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.3

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

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SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jan 22, 9:37 PM EST	Mesoscale Discussion	SPC	Dyer, Lake, Lauderdale, Obion, Shelby, Tipton	83 min
Jan 22, 10:47 PM EST	Mesoscale Discussion	SPC	Benton, Carroll, Cheatham, Chester, Crockett, Decatur and 24 more	58 min
Jan 22, 11:59 PM EST	Tornado Watch	SPC	Bedford, Benton, Cannon, Carroll, Cheatham, Chester and 44 more	7 hr
Jan 23, 2:25 AM EST	Mesoscale Discussion	SPC	Anderson, Bedford, Bledsoe, Bradley, Campbell, Cannon and 41 more	2 hr
Jan 23, 2:54 AM EST	Severe Thunderstorm Watch	SPC	Anderson, Bledsoe, Blount, Bradley, Campbell, Claiborne and 25 more	3 hr

Nearby

Mesoscale Discussions in Tennessee, 2012 Every mesoscale discussion in 2012

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.