Alert archive / Tennessee / Mesoscale Discussions in 2020
Mesoscale Discussion 476
The Storm Prediction Center issued this mesoscale discussion at Apr 25, 2020, 3:32 PM EDT for Fannin County, Murray County, Union County, Georgia; Cherokee County, Clay County, Graham County, North Carolina; 36 counties in Tennessee. It was in force for 88 min.
The area
The outline as issued.
The facts
- Issued
- Apr 25, 2020, 3:32 PM EDT (19:32 UTC)
- Expired
- Apr 25, 2020, 5:00 PM EDT
- In force
- 88 min
- Issued by
- the Storm Prediction Center
- Chance of a watch
- 40%
All 42 counties
Fannin County, GA, Murray County, GA, Union County, GA, Cherokee County, NC, Clay County, NC, Graham County, NC, Anderson County, TN, Bedford County, TN, Bledsoe County, TN, Blount County, TN, Bradley County, TN, Cannon County, TN, Clay County, TN, Coffee County, TN, Cumberland County, TN, DeKalb County, TN, Fentress County, TN, Grundy County, TN, Hamilton County, TN, Jackson County, TN, Knox County, TN, Loudon County, TN, Macon County, TN, Marion County, TN, McMinn County, TN, Meigs County, TN, Monroe County, TN, Morgan County, TN, Overton County, TN, Polk County, TN, Putnam County, TN, Rhea County, TN, Roane County, TN, Rutherford County, TN, Sequatchie County, TN, Sevier County, TN, Smith County, TN, Trousdale County, TN, Van Buren County, TN, Warren County, TN, White County, TN, Wilson County, TN
The radar
The Northeast Alabama radar (KHTX), 111 km from the middle of the area, began a volume at 19:35 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 watches that followed
Watches SPC issued over any of the same counties within four hours of this discussion.
The nearest sounding before it
Nashville Metro, TN (KBNA), launched 12:00Z, 7.5 hours before the alert went out and 139 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
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 1233 m above ground
- 0-6 km bulk shear
- 33 kt
- 0-1 km storm-relative helicity
- 108 m²/s²
- 0-3 km storm-relative helicity
- 108 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
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 |
|---|---|---|---|---|
| Apr 25, 6:11 PM EDT | Tornado Watch | SPC | Fannin, Gilmer, Habersham, Lumpkin, Rabun, Stephens and 3 more | 4 hr |
Nearby
Mesoscale Discussions in Tennessee, 2020Mesoscale Discussions in Georgia, 2020Mesoscale Discussions in North Carolina, 2020Every 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.