Alert archive / Tennessee / Mesoscale Discussions in 2009
Mesoscale Discussion 321
The Storm Prediction Center issued this mesoscale discussion at Mar 28, 2009, 5:18 PM CDT for 4 states. It was in force for 57 min.
The area
The outline as issued.
The facts
- Issued
- Mar 28, 2009, 5:18 PM CDT (22:18 UTC)
- Expired
- Mar 28, 2009, 6:15 PM CDT
- In force
- 57 min
- Issued by
- the Storm Prediction Center
All 55 counties
DeKalb County, AL, Jackson County, AL, Limestone County, AL, Madison County, AL, Marshall County, AL, Morgan County, AL, Spencer County, IN, Vanderburgh County, IN, Warrick County, IN, Allen County, KY, Breckinridge County, KY, Butler County, KY, Caldwell County, KY, Christian County, KY, Daviess County, KY, Edmonson County, KY, Grayson County, KY, Hancock County, KY, Henderson 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, Webster County, KY, Bedford County, TN, Cannon County, TN, Cheatham County, TN, Coffee County, TN, Davidson County, TN, Dickson County, TN, Franklin County, TN, Giles County, TN, Hickman County, TN, Houston County, TN, Lawrence County, TN, Lewis County, TN, Lincoln County, TN, Macon County, TN, Marshall County, TN, Maury County, TN, Montgomery County, TN, Moore County, TN, Robertson County, TN, Rutherford County, TN, Smith County, TN, Stewart County, TN, Sumner County, TN, Trousdale County, TN, Williamson County, TN, Wilson County, TN
The radar
The Nashville radar (KOHX), 48 km from the middle of the area, began a volume at 22:17 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, 10.3 hours before the alert went out and 35 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
- 5 J/kg
- Mixed-layer CIN
- -34 J/kg
- Mixed-layer LCL
- 574 m above ground
- 0-6 km bulk shear
- 32 kt
- 0-1 km storm-relative helicity
- 113 m²/s²
- 0-3 km storm-relative helicity
- 75 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 |
|---|---|---|---|---|
| Mar 27, 8:21 PM CDT | Mesoscale Discussion | SPC | Baldwin, Escambia, Mobile, Washington | 84 min |
| Mar 27, 10:09 PM CDT | Tornado Watch | SPC | Autauga, Baldwin, Butler, Choctaw, Clarke, Conecuh and 16 more | 9 hr |
| Mar 27, 11:51 PM CDT | Mesoscale Discussion | SPC | Autauga, Baldwin, Butler, Choctaw, Clarke, Conecuh and 16 more | 84 min |
| Mar 28, 1:17 AM CDT | Tornado Watch | SPC | Coffee, Dale, Geneva, Henry, Houston | 4 hr |
| Mar 28, 3:14 AM CDT | Mesoscale Discussion | SPC | Autauga, Baldwin, Butler, Chilton, Choctaw, Clarke and 17 more | 61 min |
| Mar 28, 4:25 AM CDT | Mesoscale Discussion | SPC | Autauga, Baldwin, Barbour, Bibb, Bullock, Butler and 45 more | 35 min |
| Mar 28, 4:50 AM CDT | Tornado Watch | SPC | Baldwin, Butler, Choctaw, Clarke, Coffee, Conecuh and 11 more | 5 hr |
| Mar 28, 4:59 AM CDT | Severe Thunderstorm Watch | SPC | Autauga, Barbour, Bibb, Bullock, Calhoun, Chambers and 24 more | 3 hr |
| Mar 28, 6:48 AM CDT | Mesoscale Discussion | SPC | Baldwin, Barbour, Coffee, Conecuh, Covington, Crenshaw and 6 more | 57 min |
| Mar 28, 9:20 AM CDT | Tornado Watch | SPC | Coffee, Dale, Geneva, Henry, Houston | 8 hr |
| Mar 28, 12:58 PM CDT | Mesoscale Discussion | SPC | Blount, Colbert, Cullman, Jackson, Lauderdale, Lawrence and 5 more | 92 min |
| Mar 28, 2:23 PM CDT | Tornado Watch | SPC | Cullman, DeKalb, Jackson, Lauderdale, Lawrence, Limestone and 3 more | 7 hr |
| Mar 28, 6:24 PM CDT | Tornado Watch | SPC | Clark, Crawford, Dubois, Floyd, Harrison, Jefferson and 4 more | 4 hr |
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.