Alert archive / Tennessee / Mesoscale Discussions in 2009
Mesoscale Discussion 124
The Storm Prediction Center issued this mesoscale discussion at Feb 18, 2009, 2:33 PM EST for 7 counties in Kentucky; 42 counties in Tennessee; 4 counties in Virginia. It was in force for 87 min.
The area
The outline as issued.
The facts
- Issued
- Feb 18, 2009, 2:33 PM EST (19:33 UTC)
- Expired
- Feb 18, 2009, 4:00 PM EST
- In force
- 87 min
- Issued by
- the Storm Prediction Center
All 53 counties
Bell County, KY, Harlan County, KY, Knox County, KY, Leslie County, KY, Letcher County, KY, McCreary County, KY, Whitley County, KY, Anderson County, TN, Bedford County, TN, Bledsoe County, TN, Blount County, TN, Bradley County, TN, Campbell County, TN, Cannon County, TN, Claiborne County, TN, Coffee County, TN, Cumberland County, TN, DeKalb County, TN, Fentress County, TN, Franklin County, TN, Grainger County, TN, Grundy County, TN, Hamblen County, TN, Hamilton County, TN, Hancock County, TN, Hawkins County, TN, Jackson County, TN, Jefferson County, TN, Knox County, TN, Lincoln County, TN, Loudon County, TN, Marion County, TN, McMinn County, TN, Meigs County, TN, Monroe County, TN, Moore County, TN, Morgan County, TN, Overton County, TN, Pickett County, TN, Putnam County, TN, Rhea County, TN, Roane County, TN, Scott County, TN, Sequatchie County, TN, Sevier County, TN, Union County, TN, Van Buren County, TN, Warren County, TN, White County, TN, City of Norton, VA, Lee County, VA, Scott County, VA, Wise County, VA
The radar
The Knoxville radar (KMRX), 103 km from the middle of the area, began a volume at 19:34 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, 7.6 hours before the alert went out and 186 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
- 519 m above ground
- 0-6 km bulk shear
- 78 kt
- 0-1 km storm-relative helicity
- 599 m²/s²
- 0-3 km storm-relative helicity
- 631 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
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</html>SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Feb 18, 10:53 AM EST | Mesoscale Discussion | SPC | Adair, Allen, Barren, Boyle, Casey, Clinton and 14 more | 97 min |
| Feb 18, 12:09 PM EST | Tornado Watch | SPC | Adair, Allen, Barren, Bell, Boyle, Breathitt and 51 more | 6 hr |
| Feb 18, 2:09 PM EST | Mesoscale Discussion | SPC | Boone, Bracken, Campbell, Carroll, Fleming, Gallatin and 11 more | 51 min |
| Feb 17, 8:09 PM EST | Severe Thunderstorm Watch | SPC | Fayette, Shelby, Tipton | 6 hr |
| Feb 17, 10:45 PM EST | Mesoscale Discussion | SPC | Carroll, Chester, Crockett, Decatur, Dyer, Fayette and 11 more | 2 hr |
| Feb 18, 4:22 PM EST | Mesoscale Discussion | SPC | Bradley, Franklin, Giles, Hamilton, Lincoln, Marion and 2 more | 83 min |
| Feb 18, 1:05 AM EST | Mesoscale Discussion | SPC | Albemarle, Alleghany, Amherst, Augusta, Bath, Botetourt and 24 more | 4 hr |
Nearby
Mesoscale Discussions in Tennessee, 2009Mesoscale Discussions in Kentucky, 2009Mesoscale Discussions in Virginia, 2009Every mesoscale discussion in 2009
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.