Alert archive / Tennessee / Severe Thunderstorm Watches in 2012
Severe Thunderstorm Watch 189
The Storm Prediction Center issued this severe thunderstorm watch at Apr 26, 2012, 6:22 AM EDT for McCreary County, Wayne County, Whitley County, Kentucky; 50 counties in Tennessee. It was in force for 3 hr.
The area
The outline as issued.
The facts
- Issued
- Apr 26, 2012, 6:22 AM EDT (10:22 UTC)
- Expired
- Apr 26, 2012, 9:42 AM EDT
- In force
- 3 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 1 in
- Strongest gust expected
- 60 kt
All 53 counties
McCreary County, KY, Wayne County, KY, Whitley County, KY, Anderson County, TN, Bedford County, TN, Bledsoe County, TN, Blount County, TN, Campbell County, TN, Cannon County, TN, Carter County, TN, Claiborne County, TN, Clay County, TN, Cocke County, TN, Coffee County, TN, Cumberland County, TN, DeKalb County, TN, Fentress County, TN, Grainger County, TN, Greene County, TN, Grundy County, TN, Hamblen County, TN, Hancock County, TN, Hawkins County, TN, Jackson County, TN, Jefferson County, TN, Johnson County, TN, Knox County, TN, Loudon County, TN, Macon County, TN, McMinn County, TN, Meigs County, TN, Monroe County, TN, Morgan County, TN, Overton County, TN, Pickett County, TN, Putnam County, TN, Rhea County, TN, Roane County, TN, Rutherford County, TN, Scott County, TN, Sequatchie County, TN, Sevier County, TN, Smith County, TN, Sullivan County, TN, Sumner County, TN, Trousdale County, TN, Unicoi County, TN, Union County, TN, Van Buren County, TN, Warren County, TN, Washington County, TN, White County, TN, Wilson County, TN
The radar
The Knoxville radar (KMRX), 130 km from the middle of the area, began a volume at 10:25 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.
What SPC expected
The probabilities SPC published with the watch, for the watch area over its life.
- Two or more tornadoes
- 20%
- One or more EF2 to EF5 tornadoes
- 5%
- Ten or more severe wind reports
- 30%
- One or more gusts of 65 knots or more
- 30%
- Ten or more severe hail reports
- 30%
- One or more hailstones of 2 inches or more
- 10%
- Six or more combined severe hail and wind reports
- 70%
Warnings issued inside it
14 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 26, 6:24 AM EDT | Severe Thunderstorm Warning | OHX | Clay, Cumberland, Fentress, Jackson, Macon, Overton and 6 more | 51 min |
| Apr 26, 6:27 AM EDT | Severe Thunderstorm Warning | JKL | Bell, Clay, Harlan, Knox, Laurel, Leslie and 2 more | 48 min |
| Apr 26, 6:44 AM EDT | Severe Thunderstorm Warning | MRX | Anderson, Campbell, Claiborne, Grainger, Knox, Morgan and 2 more | 46 min |
| Apr 26, 6:51 AM EDT | Severe Thunderstorm Warning | MRX | Hancock, Hawkins | 54 min |
| Apr 26, 7:07 AM EDT | Severe Thunderstorm Warning | MRX | Blount, Knox, Loudon, Monroe, Roane, Sevier | 53 min |
| Apr 26, 7:13 AM EDT | Severe Thunderstorm Warning | MRX | Cocke, Greene, Hamblen, Hawkins, Jefferson | 62 min |
| Apr 26, 7:15 AM EDT | Severe Thunderstorm Warning | OHX | Cumberland, DeKalb, Putnam, Smith, Van Buren, White | 45 min |
| Apr 26, 7:31 AM EDT | Severe Thunderstorm Warning | MRX | Grainger | 14 min |
| Apr 26, 7:37 AM EDT | Severe Thunderstorm Warning | MRX | Bledsoe, McMinn, Meigs, Monroe, Rhea | 53 min |
| Apr 26, 7:42 AM EDT | Severe Thunderstorm Warning | MRX | Greene, Hancock, Hawkins, Sullivan, Washington | 53 min |
| Apr 26, 7:58 AM EDT | Severe Thunderstorm Warning | MRX | Blount, Loudon, Monroe, Roane, Sevier | 47 min |
| Apr 26, 8:00 AM EDT | Severe Thunderstorm Warning | OHX | Cumberland, Van Buren, White | 30 min |
| Apr 26, 8:11 AM EDT | Severe Thunderstorm Warning | MRX | Carter, Johnson, Sullivan, Unicoi | 46 min |
| Apr 26, 8:30 AM EDT | Severe Thunderstorm Warning | MRX | Bledsoe, McMinn, Meigs, Monroe, Rhea | 60 min |
Discussions around it
SPC mesoscale discussions over the same counties from four hours before the watch to its end.
The nearest sounding before it
Nashville Metro, TN (KBNA), launched 00:00Z, 10.4 hours before the alert went out and 158 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
- 1411 J/kg
- Mixed-layer CIN
- -108 J/kg
- Mixed-layer LCL
- 1242 m above ground
- 0-6 km bulk shear
- 51 kt
- 0-1 km storm-relative helicity
- 250 m²/s²
- 0-3 km storm-relative helicity
- 383 m²/s²
- Significant tornado parameter
- 1.3
- Supercell composite
- 4.7
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 25, 11:11 PM EDT | Mesoscale Discussion | SPC | Anderson, Bath, Boone, Bourbon, Boyd, Boyle and 72 more | 2 hr |
| Apr 26, 1:40 AM EDT | Severe Thunderstorm Watch | SPC | Adair, Allen, Anderson, Barren, Bourbon, Boyle and 53 more | 6 hr |
| Apr 26, 3:23 AM EDT | Mesoscale Discussion | SPC | Anderson, Barren, Boyle, Breckinridge, Bullitt, Butler and 30 more | 97 min |
| Apr 26, 5:07 AM EDT | Mesoscale Discussion | SPC | Bell, Clay, Knox, Laurel, Leslie, McCreary and 1 more | 83 min |
| Apr 26, 7:24 AM EDT | Mesoscale Discussion | SPC | Bell, Harlan, Leslie, Letcher, Perry | 96 min |
| Apr 26, 2:23 PM EDT | Mesoscale Discussion | SPC | Adair, Allen, Barren, Bath, Bell, Boyd and 61 more | 2 hr |
| Apr 26, 3:11 PM EDT | Severe Thunderstorm Watch | SPC | Adair, Allen, Barren, Bell, Breathitt, Calloway and 42 more | 6 hr |
| Apr 26, 4:22 PM EDT | Mesoscale Discussion | SPC | Adair, Allen, Barren, Bell, Breathitt, Clay and 26 more | 83 min |
| Apr 26, 6:40 PM EDT | Mesoscale Discussion | SPC | Adair, Allen, Barren, Bell, Breathitt, Clay and 23 more | 95 min |
| Apr 26, 8:10 AM EDT | Severe Thunderstorm Watch | SPC | Bradley, Hamilton, Polk | 3 hr |
| Apr 26, 8:47 AM EDT | Mesoscale Discussion | SPC | Blount, Bradley, Carter, Johnson, Loudon, McMinn and 6 more | 88 min |
| Apr 26, 5:52 PM EDT | Mesoscale Discussion | SPC | Benton, Carroll, Chester, Crockett, Decatur, Dickson and 13 more | 83 min |
| Apr 26, 7:09 PM EDT | Mesoscale Discussion | SPC | Bradley, Polk | 96 min |
Nearby
Severe Thunderstorm Watches in Tennessee, 2012Severe Thunderstorm Watches in Kentucky, 2012Every severe thunderstorm watch in 2012
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.