Alert archive / Tennessee / Mesoscale Discussions in 2017
Mesoscale Discussion 1773
The Storm Prediction Center issued this mesoscale discussion at Nov 18, 2017, 5:24 PM CST for 10 counties in Alabama; 31 counties in Tennessee. It was in force for 2 hr.
The area
The outline as issued.
The facts
- Issued
- Nov 18, 2017, 5:24 PM CST (23:24 UTC)
- Expired
- Nov 18, 2017, 7:30 PM CST
- In force
- 2 hr
- Issued by
- the Storm Prediction Center
All 41 counties
Cullman County, AL, Franklin County, AL, Jackson County, AL, Lawrence County, AL, Limestone County, AL, Madison County, AL, Marion County, AL, Marshall County, AL, Morgan County, AL, Winston County, AL, Bedford County, TN, Bledsoe County, TN, Cannon County, TN, Clay County, TN, Coffee County, TN, Cumberland County, TN, DeKalb County, TN, Fentress County, TN, Franklin County, TN, Giles County, TN, Grundy County, TN, Jackson County, TN, Lincoln County, TN, Macon County, TN, Marion County, TN, Marshall County, TN, Moore County, TN, Morgan County, TN, Overton County, TN, Pickett County, TN, Putnam County, TN, Rhea County, TN, Rutherford County, TN, Scott County, TN, Sequatchie 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), 32 km from the middle of the area, began a volume at 23:27 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 12:00Z, 11.4 hours before the alert went out and 131 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
- 858 m above ground
- 0-6 km bulk shear
- 59 kt
- 0-1 km storm-relative helicity
- 559 m²/s²
- 0-3 km storm-relative helicity
- 544 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 |
|---|---|---|---|---|
| Nov 18, 3:18 PM CST | Mesoscale Discussion | SPC | Colbert, Cullman, Franklin, Lauderdale, Lawrence, Limestone and 5 more | 117 min |
| Nov 18, 10:24 AM CST | Mesoscale Discussion | SPC | Dyer, Lake, Lauderdale, Obion, Weakley | 2 hr |
| Nov 18, 12:35 PM CST | Severe Thunderstorm Watch | SPC | Bedford, Benton, Cannon, Carroll, Cheatham, Chester and 53 more | 6 hr |
Nearby
Mesoscale Discussions in Tennessee, 2017Mesoscale Discussions in Alabama, 2017Every mesoscale discussion in 2017
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.