Alert archive / Tennessee / Mesoscale Discussions in 2020

Mesoscale Discussion 902

June 10, 20204 states

The Storm Prediction Center issued this mesoscale discussion at Jun 10, 2020, 6:23 PM EDT for 4 states. It was in force for 97 min.

The area

The outline as issued.

The facts

Issued: Jun 10, 2020, 6:23 PM EDT (22:23 UTC)
Expired: Jun 10, 2020, 8:00 PM EDT
In force: 97 min
Issued by: the Storm Prediction Center
Concerning: Severe potential...watch unlikely
Chance of a watch: 20%

All 43 counties

Bell County, KY, Harlan County, KY, Letcher County, KY, Whitley County, KY, Graham County, NC, Swain County, NC, Anderson County, TN, Blount County, TN, Bradley County, TN, Campbell County, TN, Claiborne County, TN, Cocke County, TN, Cumberland County, TN, Fentress County, TN, Grainger County, TN, Greene 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, Morgan County, TN, Polk County, TN, Rhea County, TN, Roane County, TN, Scott County, TN, Sevier County, TN, Sullivan County, TN, Union County, TN, Washington County, TN, Buchanan County, VA, City of Bristol, VA, City of Norton, VA, Dickenson County, VA, Lee County, VA, Russell County, VA, Scott County, VA, Wise County, VA

The radar

The Knoxville radar (KMRX), 21 km from the middle of the area, began a volume at 22:25 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

Cncnati-Daytn, OH (KILN), launched 12:00Z, 10.4 hours before the alert went out and 344 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: 346 J/kg
Mixed-layer CIN: -192 J/kg
Mixed-layer LCL: 774 m above ground
0-6 km bulk shear: 15 kt
0-1 km storm-relative helicity: 205 m²/s²
0-3 km storm-relative helicity: 116 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

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SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jun 10, 11:54 AM EDT	Severe Thunderstorm Watch	SPC	Anderson, Bourbon, Boyle, Casey, Clark, Fayette and 20 more	6 hr
Jun 10, 1:58 PM EDT	Mesoscale Discussion	SPC	Boone, Bracken, Campbell, Carroll, Gallatin, Grant and 6 more	92 min
Jun 10, 2:48 PM EDT	Severe Thunderstorm Watch	SPC	Boone, Bracken, Campbell, Carroll, Gallatin, Grant and 6 more	6 hr
Jun 10, 5:30 PM EDT	Severe Thunderstorm Watch	SPC	Bath, Bell, Breathitt, Clay, Elliott, Estill and 25 more	5 hr
Jun 10, 6:35 PM EDT	Mesoscale Discussion	SPC	Boyd, Greenup	85 min
Jun 10, 6:51 PM EDT	Severe Thunderstorm Watch	SPC	Boyd, Carter, Greenup, Lawrence	6 hr
Jun 10, 7:45 PM EDT	Mesoscale Discussion	SPC	Boyd, Breathitt, Carter, Elliott, Floyd, Greenup and 9 more	90 min

Nearby

Mesoscale Discussions in Tennessee, 2020 Mesoscale Discussions in Virginia, 2020 Mesoscale Discussions in Kentucky, 2020 Every mesoscale discussion in 2020

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.