Alert archive / Tennessee / Mesoscale Discussions in 2018
Mesoscale Discussion 1111
The Storm Prediction Center issued this mesoscale discussion at Jul 20, 2018, 10:52 PM EDT for 4 states. It was in force for 53 min.
The area
The outline as issued.
The facts
- Issued
- Jul 20, 2018, 10:52 PM EDT (02:52 UTC)
- Expired
- Jul 20, 2018, 11:45 PM EDT
- In force
- 53 min
- Issued by
- the Storm Prediction Center
All 55 counties
Bell County, KY, Clinton County, KY, Harlan County, KY, Knox County, KY, McCreary County, KY, Wayne County, KY, Whitley County, KY, Cherokee County, NC, Graham County, NC, Madison County, NC, Swain County, NC, Anderson County, TN, Bledsoe County, TN, Blount County, TN, Bradley County, TN, Campbell County, TN, Carter County, TN, Claiborne County, TN, Clay 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, Johnson County, TN, Knox County, TN, Loudon County, TN, McMinn County, TN, Meigs County, TN, Monroe County, TN, Morgan County, TN, Overton County, TN, Pickett County, TN, Polk County, TN, Putnam County, TN, Rhea County, TN, Roane County, TN, Scott County, TN, Sequatchie County, TN, Sevier County, TN, Sullivan County, TN, Unicoi County, TN, Union County, TN, Van Buren County, TN, Washington County, TN, White County, TN, City of Bristol, VA, Lee County, VA, Scott County, VA, Washington County, VA
The radar
The Knoxville radar (KMRX), 49 km from the middle of the area, began a volume at 02:52 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, 2.9 hours before the alert went out and 239 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.
- Mixed-layer CAPE
- 3305 J/kg
- Mixed-layer CIN
- -1 J/kg
- Mixed-layer LCL
- 1217 m above ground
- 0-6 km bulk shear
- 53 kt
- 0-1 km storm-relative helicity
- 90 m²/s²
- 0-3 km storm-relative helicity
- 169 m²/s²
- Significant tornado parameter
- 2.2
- Supercell composite
- 11.6
The text
As transmitted.
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</html>SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 20, 11:20 PM EDT | Mesoscale Discussion | SPC | Adair, Allen, Ballard, Barren, Breckinridge, Bullitt and 43 more | 115 min |
| Jul 21, 2:38 AM EDT | Mesoscale Discussion | SPC | Allen, Barren, Calloway, Christian, Clinton, Cumberland and 6 more | 67 min |
| Jul 21, 3:00 AM EDT | Severe Thunderstorm Watch | SPC | Cherokee, Clay | 7 hr |
| Jul 21, 3:37 PM EDT | Mesoscale Discussion | SPC | Buncombe, Cherokee, Clay, Graham, Haywood, Henderson and 7 more | 2 hr |
| Jul 21, 5:42 PM EDT | Severe Thunderstorm Watch | SPC | Cleveland, Gaston, Lincoln, Polk, Rutherford | 8 hr |
| Jul 21, 7:24 PM EDT | Mesoscale Discussion | SPC | Cleveland, Henderson, Polk, Rutherford, Transylvania | 96 min |
| Jul 20, 8:02 PM EDT | Tornado Watch | SPC | Anderson, Bledsoe, Blount, Bradley, Campbell, Claiborne and 22 more | 7 hr |
| Jul 21, 5:35 AM EDT | Mesoscale Discussion | SPC | Bedford, Bledsoe, Cannon, Coffee, DeKalb, Franklin and 14 more | 115 min |
Nearby
Mesoscale Discussions in Tennessee, 2018Mesoscale Discussions in Kentucky, 2018Mesoscale Discussions in North Carolina, 2018Every mesoscale discussion 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.