Alert archive / Tennessee / Mesoscale Discussions in 2018
Mesoscale Discussion 128
The Storm Prediction Center issued this mesoscale discussion at Mar 17, 2018, 6:06 PM EDT for 8 counties in Georgia; Cherokee County, Clay County, Graham County, North Carolina; 13 counties in Tennessee. It was in force for 114 min.
The area
The outline as issued.
The facts
- Issued
- Mar 17, 2018, 6:06 PM EDT (22:06 UTC)
- Expired
- Mar 17, 2018, 8:00 PM EDT
- In force
- 114 min
- Issued by
- the Storm Prediction Center
- Chance of a watch
- 20%
All 24 counties
Catoosa County, GA, Dade County, GA, Fannin County, GA, Gilmer County, GA, Murray County, GA, Union County, GA, Walker County, GA, Whitfield County, GA, Cherokee County, NC, Clay County, NC, Graham County, NC, Bledsoe County, TN, Bradley County, TN, Coffee County, TN, Franklin County, TN, Grundy County, TN, Hamilton County, TN, Marion County, TN, McMinn County, TN, Meigs County, TN, Monroe County, TN, Polk County, TN, Rhea County, TN, Sequatchie County, TN
The radar
The Northeast Alabama radar (KHTX), 84 km from the middle of the area, began a volume at 22:09 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, 10.1 hours before the alert went out and 162 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
- 69 J/kg
- Mixed-layer CIN
- -106 J/kg
- Mixed-layer LCL
- 772 m above ground
- 0-6 km bulk shear
- 53 kt
- 0-1 km storm-relative helicity
- 138 m²/s²
- 0-3 km storm-relative helicity
- 118 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.2
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 |
|---|---|---|---|---|
| Mar 17, 4:33 PM EDT | Severe Thunderstorm Watch | SPC | Ashe, Avery, Madison, Mitchell, Watauga, Yancey | 7 hr |
| Mar 17, 7:06 PM EDT | Mesoscale Discussion | SPC | Madison, Mitchell, Yancey | 114 min |
| Mar 17, 12:46 AM EDT | Mesoscale Discussion | SPC | Montgomery, Obion, Stewart | 59 min |
| Mar 17, 3:25 PM EDT | Mesoscale Discussion | SPC | Campbell, Carter, Claiborne, Cocke, Fentress, Grainger and 12 more | 2 hr |
Nearby
Mesoscale Discussions in Tennessee, 2018Mesoscale Discussions in Georgia, 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.