Alert archive / Tennessee / Mesoscale Discussions in 2016
Mesoscale Discussion 1899
The Storm Prediction Center issued this mesoscale discussion at Dec 18, 2016, 3:24 AM CST for 7 counties in Alabama; 5 counties in Georgia; 17 counties in Tennessee. It was in force for 66 min.
The area
The outline as issued.
The facts
- Issued
- Dec 18, 2016, 3:24 AM CST (09:24 UTC)
- Expired
- Dec 18, 2016, 4:30 AM CST
- In force
- 66 min
- Issued by
- the Storm Prediction Center
All 29 counties
Blount County, AL, Cullman County, AL, DeKalb County, AL, Etowah County, AL, Jackson County, AL, Marshall County, AL, Walker County, AL, Catoosa County, GA, Chattooga County, GA, Dade County, GA, Walker County, GA, Whitfield County, GA, Anderson County, TN, Bledsoe County, TN, Bradley County, TN, Campbell County, TN, Claiborne County, TN, Grainger County, TN, Hamilton County, TN, Knox County, TN, Loudon County, TN, Marion County, TN, McMinn County, TN, Meigs County, TN, Morgan County, TN, Rhea County, TN, Roane County, TN, Sequatchie County, TN, Union County, TN
The radar
The Northeast Alabama radar (KHTX), 50 km from the middle of the area, began a volume at 09:27 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, 9.4 hours before the alert went out and 170 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
- 26 J/kg
- Mixed-layer CIN
- -109 J/kg
- Mixed-layer LCL
- 692 m above ground
- 0-6 km bulk shear
- 81 kt
- 0-1 km storm-relative helicity
- 511 m²/s²
- 0-3 km storm-relative helicity
- 473 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.1
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 |
|---|---|---|---|---|
| Dec 17, 8:28 PM CST | Mesoscale Discussion | SPC | Colbert, Franklin, Lauderdale, Lawrence, Limestone, Marion | 62 min |
| Dec 17, 8:58 PM CST | Tornado Watch | SPC | Colbert, Franklin, Lauderdale, Lawrence, Limestone | 6 hr |
| Dec 17, 11:48 PM CST | Mesoscale Discussion | SPC | Colbert, Franklin, Lamar, Lauderdale, Lawrence, Limestone and 1 more | 87 min |
| Dec 18, 1:03 AM CST | Severe Thunderstorm Watch | SPC | Blount, Cullman, DeKalb, Fayette, Jackson, Lamar and 7 more | 4 hr |
| Dec 18, 2:30 AM CST | Mesoscale Discussion | SPC | Colbert, Lauderdale | 4 hr |
Nearby
Mesoscale Discussions in Tennessee, 2016Mesoscale Discussions in Alabama, 2016Mesoscale Discussions in Georgia, 2016Every mesoscale discussion in 2016
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.