Alert archive / Tennessee / Mesoscale Discussions in 2009
Mesoscale Discussion 466
The Storm Prediction Center issued this mesoscale discussion at Apr 13, 2009, 12:09 PM CDT for 4 states. It was in force for 66 min.
The area
The outline as issued.
The facts
- Issued
- Apr 13, 2009, 12:09 PM CDT (17:09 UTC)
- Expired
- Apr 13, 2009, 1:15 PM CDT
- In force
- 66 min
- Issued by
- the Storm Prediction Center
All 64 counties
Colbert County, AL, Franklin County, AL, Lauderdale County, AL, Lawrence County, AL, Limestone County, AL, Marion County, AL, Morgan County, AL, Winston County, AL, Allen County, KY, Barren County, KY, Breckinridge County, KY, Butler County, KY, Christian County, KY, Daviess County, KY, Edmonson County, KY, Grayson County, KY, Hancock County, KY, Hardin County, KY, Hart County, KY, Hopkins County, KY, Logan County, KY, McLean County, KY, Muhlenberg County, KY, Ohio County, KY, Simpson County, KY, Todd County, KY, Trigg County, KY, Warren County, KY, Alcorn County, MS, Itawamba County, MS, Prentiss County, MS, Tishomingo County, MS, Bedford County, TN, Benton County, TN, Cannon County, TN, Cheatham County, TN, Davidson County, TN, Decatur County, TN, Dickson County, TN, Giles County, TN, Hardin County, TN, Henderson County, TN, Hickman County, TN, Houston County, TN, Humphreys County, TN, Lawrence County, TN, Lewis County, TN, Lincoln County, TN, Macon County, TN, Marshall County, TN, Maury County, TN, McNairy County, TN, Montgomery County, TN, Moore County, TN, Perry County, TN, Robertson County, TN, Rutherford County, TN, Smith County, TN, Stewart County, TN, Sumner County, TN, Trousdale County, TN, Wayne County, TN, Williamson County, TN, Wilson County, TN
The radar
The Nashville radar (KOHX), 55 km from the middle of the area, began a volume at 17:07 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, 5.2 hours before the alert went out and 47 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
- 730 m above ground
- 0-6 km bulk shear
- 87 kt
- 0-1 km storm-relative helicity
- 366 m²/s²
- 0-3 km storm-relative helicity
- 512 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 |
|---|---|---|---|---|
| Apr 12, 8:07 PM CDT | Mesoscale Discussion | SPC | Autauga, Bibb, Butler, Chilton, Choctaw, Clarke and 12 more | 53 min |
| Apr 12, 8:30 PM CDT | Tornado Watch | SPC | Choctaw, Clarke, Greene, Hale, Marengo, Mobile and 2 more | 6 hr |
| Apr 12, 10:42 PM CDT | Mesoscale Discussion | SPC | Autauga, Baldwin, Barbour, Bibb, Bullock, Butler and 33 more | 93 min |
| Apr 12, 11:01 PM CDT | Tornado Watch | SPC | Autauga, Baldwin, Butler, Conecuh, Covington, Crenshaw and 8 more | 4 hr |
| Apr 13, 1:57 AM CDT | Mesoscale Discussion | SPC | Baldwin, Barbour, Bullock, Butler, Coffee, Conecuh and 13 more | 63 min |
| Apr 13, 2:33 AM CDT | Tornado Watch | SPC | Baldwin, Barbour, Bullock, Butler, Clarke, Coffee and 14 more | 7 hr |
| Apr 13, 4:32 AM CDT | Mesoscale Discussion | SPC | Baldwin, Barbour, Bullock, Butler, Coffee, Conecuh and 10 more | 58 min |
| Apr 13, 7:27 AM CDT | Mesoscale Discussion | SPC | Baldwin, Coffee, Covington, Dale, Escambia, Geneva and 3 more | 2 hr |
| Apr 13, 9:12 AM CDT | Tornado Watch | SPC | Coffee, Covington, Dale, Escambia, Geneva, Henry and 1 more | 9 hr |
| Apr 13, 11:15 AM CDT | Mesoscale Discussion | SPC | Baldwin, Barbour, Bullock, Butler, Clarke, Coffee and 11 more | 90 min |
| Apr 13, 12:58 PM CDT | Tornado Watch | SPC | Colbert, Cullman, DeKalb, Franklin, Jackson, Lauderdale and 5 more | 7 hr |
| Apr 13, 4:16 PM CDT | Severe Thunderstorm Watch | SPC | Choctaw | 4 hr |
| Apr 13, 5:52 PM CDT | Mesoscale Discussion | SPC | Blount, Cullman, DeKalb, Etowah, Fayette, Jackson and 10 more | 53 min |
| Apr 13, 6:55 PM CDT | Mesoscale Discussion | SPC | Bibb, Chilton, Choctaw, Clarke, Dallas, Greene and 9 more | 95 min |
| Apr 13, 3:22 PM CDT | Mesoscale Discussion | SPC | Adair, Allen, Anderson, Barren, Boyle, Breckinridge and 29 more | 53 min |
| Apr 13, 1:39 PM CDT | Mesoscale Discussion | SPC | Adams, Amite, Copiah, Covington, Forrest, Franklin and 14 more | 66 min |
Nearby
Mesoscale Discussions in Tennessee, 2009Mesoscale Discussions in Kentucky, 2009Mesoscale Discussions in Alabama, 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.