Alert archive / Kentucky / Severe Thunderstorm Watches in 2011

Severe Thunderstorm Watch 112

April 9, 20115 states

The Storm Prediction Center issued this severe thunderstorm watch at Apr 9, 2011, 12:34 PM EDT for 5 states. It was in force for 4 hr.

The area

The outline as issued.

The facts

Issued
Apr 9, 2011, 12:34 PM EDT (16:34 UTC)
Expired
Apr 9, 2011, 4:23 PM EDT
In force
4 hr
Issued by
the Storm Prediction Center
Largest hail expected
2 in
Strongest gust expected
70 kt
All 123 counties

Bath County, KY, Bell County, KY, Boyd County, KY, Breathitt County, KY, Carter County, KY, Clay County, KY, Elliott County, KY, Estill County, KY, Fleming County, KY, Floyd County, KY, Harlan County, KY, Jackson County, KY, Johnson County, KY, Knott County, KY, Knox County, KY, Laurel County, KY, Lawrence County, KY, Lee County, KY, Leslie County, KY, Letcher County, KY, Magoffin County, KY, Martin County, KY, McCreary County, KY, Menifee County, KY, Montgomery County, KY, Morgan County, KY, Owsley County, KY, Perry County, KY, Pike County, KY, Powell County, KY, Pulaski County, KY, Rockcastle County, KY, Rowan County, KY, Wayne County, KY, Whitley County, KY, Wolfe County, KY, Alleghany County, NC, Ashe County, NC, Avery County, NC, Buncombe County, NC, Burke County, NC, Caldwell County, NC, Cherokee County, NC, Clay County, NC, Graham County, NC, Haywood County, NC, Henderson County, NC, Jackson County, NC, Macon County, NC, Madison County, NC, McDowell County, NC, Mitchell County, NC, Polk County, NC, Rutherford County, NC, Swain County, NC, Transylvania County, NC, Watauga County, NC, Wilkes County, NC, Yancey County, NC, Anderson County, TN, Blount County, TN, Bradley County, TN, Campbell County, TN, Carter County, TN, Claiborne County, TN, Cocke County, TN, Grainger County, TN, Greene County, TN, Hamblen County, TN, Hamilton County, TN, Hancock County, TN, Hawkins County, TN, Jefferson County, TN, Johnson County, TN, Knox County, TN, Loudon County, TN, McMinn County, TN, Meigs County, TN, Monroe County, TN, Morgan County, TN, Polk County, TN, Rhea County, TN, Roane County, TN, Scott County, TN, Sevier County, TN, Sullivan County, TN, Unicoi County, TN, Union County, TN, Washington County, TN, Bland County, VA, Buchanan County, VA, Carroll County, VA, City of Bristol, VA, City of Galax, VA, City of Norton, VA, Dickenson County, VA, Giles County, VA, Grayson County, VA, Lee County, VA, Pulaski County, VA, Russell County, VA, Scott County, VA, Smyth County, VA, Tazewell County, VA, Washington County, VA, Wise County, VA, Wythe County, VA, Boone County, WV, Cabell County, WV, Fayette County, WV, Greenbrier County, WV, Kanawha County, WV, Lincoln County, WV, Logan County, WV, McDowell County, WV, Mercer County, WV, Mingo County, WV, Monroe County, WV, Putnam County, WV, Raleigh County, WV, Summers County, WV, Wayne County, WV, Wyoming County, WV

The radar

The Jackson,KY radar (KJKL), 67 km from the middle of the area, began a volume at 16:35 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
80%
One or more gusts of 65 knots or more
50%
Ten or more severe hail reports
70%
One or more hailstones of 2 inches or more
40%
Six or more combined severe hail and wind reports
95%

Warnings issued inside it

62 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
Apr 9, 1:09 PM EDTSevere Thunderstorm WarningGSPBuncombe, McDowell, Yancey42 min
Apr 9, 1:14 PM EDTSevere Thunderstorm WarningJKLFloyd, Knott, Letcher, Pike46 min
Apr 9, 1:27 PM EDTSevere Thunderstorm WarningRLXLawrence48 min
Apr 9, 1:38 PM EDTSevere Thunderstorm WarningGSPMcDowell, Mitchell, Yancey52 min
Apr 9, 1:40 PM EDTSevere Thunderstorm WarningJKLPulaski, Rockcastle50 min
Apr 9, 1:44 PM EDTTornado WarningJKLEstill, Menifee, Montgomery, Powell, Wolfe31 min
Apr 9, 1:48 PM EDTSevere Thunderstorm WarningJKLEstill, Lee, Menifee, Powell, Wolfe42 min
Apr 9, 1:50 PM EDTSevere Thunderstorm WarningJKLFloyd, Pike40 min
Apr 9, 1:51 PM EDTSevere Thunderstorm WarningJKLFloyd, Knott, Letcher, Pike28 min
Apr 9, 1:54 PM EDTTornado WarningJKLLaurel, Pulaski, Rockcastle36 min
Apr 9, 1:58 PM EDTSevere Thunderstorm WarningJKLEstill, Jackson, Lee, Owsley, Rockcastle47 min
Apr 9, 2:01 PM EDTSevere Thunderstorm WarningJKLBath, Elliott, Menifee, Montgomery, Morgan, Rowan44 min
Apr 9, 2:05 PM EDTTornado WarningJKLElliott, Magoffin, Menifee, Morgan, Wolfe40 min
Apr 9, 2:10 PM EDTSevere Thunderstorm WarningGSPBuncombe, Madison, Yancey24 min
Apr 9, 2:11 PM EDTSevere Thunderstorm WarningRLXLawrence64 min
Apr 9, 2:18 PM EDTSevere Thunderstorm WarningRLXBuchanan, Dickenson57 min
Apr 9, 2:20 PM EDTSevere Thunderstorm WarningJKLBreathitt, Floyd, Knott, Lee, Magoffin, Morgan and 1 more40 min
Apr 9, 2:21 PM EDTSevere Thunderstorm WarningGSPAvery, Burke, Caldwell, Mitchell42 min
Apr 9, 2:21 PM EDTSevere Thunderstorm WarningRLXBoone, Logan, Mingo54 min
Apr 9, 2:23 PM EDTSevere Thunderstorm WarningJKLClay, Jackson, Knox, Laurel, Pulaski, Rockcastle37 min
Apr 9, 2:24 PM EDTSevere Thunderstorm WarningMRXRussell, Washington, City of Bristol51 min
Apr 9, 2:27 PM EDTTornado WarningJKLFloyd, Johnson, Magoffin, Morgan33 min
Apr 9, 2:31 PM EDTTornado WarningJKLClay, Knox, Laurel, Pulaski44 min
Apr 9, 2:32 PM EDTTornado WarningJKLClay, Jackson, Laurel, Owsley43 min
Apr 9, 2:33 PM EDTSevere Thunderstorm WarningGSPAvery, Burke, McDowell, Mitchell, Yancey57 min
Apr 9, 2:36 PM EDTSevere Thunderstorm WarningJKLKnox, Laurel, McCreary, Pulaski, Wayne, Whitley24 min
Apr 9, 2:40 PM EDTSevere Thunderstorm WarningGSPBurke, Caldwell28 min
Apr 9, 2:43 PM EDTSevere Thunderstorm WarningJKLBreathitt, Clay, Floyd, Johnson, Knott, Lee and 6 more47 min
Apr 9, 2:43 PM EDTSevere Thunderstorm WarningRLXBuchanan62 min
Apr 9, 2:50 PM EDTSevere Thunderstorm WarningRNKCarroll, Grayson, Smyth, Wythe85 min
Apr 9, 2:53 PM EDTSevere Thunderstorm WarningRNKAshe, Surry, Watauga, Wilkes, Yadkin67 min
Apr 9, 2:53 PM EDTTornado WarningMRXWashington24 min
Apr 9, 2:56 PM EDTTornado WarningRNKSmyth34 min
Apr 9, 2:58 PM EDTSevere Thunderstorm WarningJKLBell, Clay, Harlan, Knox, Laurel, Leslie and 1 more32 min
Apr 9, 3:01 PM EDTSevere Thunderstorm WarningJKLBreathitt, Clay, Leslie, Owsley, Perry29 min
Apr 9, 3:03 PM EDTSevere Thunderstorm WarningMRXJohnson27 min
Apr 9, 3:05 PM EDTFlash Flood WarningJKLPike4 hr
Apr 9, 3:10 PM EDTSevere Thunderstorm WarningJKLBell, Harlan, Knox, Laurel, Leslie, Whitley50 min
Apr 9, 3:12 PM EDTSevere Thunderstorm WarningGSPBuncombe, McDowell, Yancey48 min
Apr 9, 3:14 PM EDTSevere Thunderstorm WarningJKLBreathitt, Floyd, Johnson, Knott, Letcher, Magoffin and 3 more46 min
Apr 9, 3:15 PM EDTSevere Thunderstorm WarningRLXBoone, Kanawha, Lincoln, Logan29 min
Apr 9, 3:18 PM EDTSevere Thunderstorm WarningRNKBland, Smyth, Tazewell, Wythe57 min
Apr 9, 3:20 PM EDTSevere Thunderstorm WarningRNKAlleghany, Ashe, Surry, Watauga, Wilkes, Yadkin55 min
Apr 9, 3:21 PM EDTTornado WarningJKLKnott, Leslie, Letcher, Perry, Pike39 min
Apr 9, 3:23 PM EDTTornado WarningRNKGrayson, Smyth22 min
Apr 9, 3:26 PM EDTTornado WarningJKLBell, Harlan, Leslie, Letcher, Perry34 min
Apr 9, 3:27 PM EDTTornado WarningRNKAlleghany, Ashe33 min
Apr 9, 3:30 PM EDTTornado WarningJKLFloyd, Pike45 min
Apr 9, 3:37 PM EDTTornado WarningMRXWise, City of Norton38 min
Apr 9, 3:40 PM EDTSevere Thunderstorm WarningRLXBuchanan, Dickenson65 min
Apr 9, 3:41 PM EDTSevere Thunderstorm WarningMRXHancock, Hawkins64 min
Apr 9, 3:42 PM EDTSevere Thunderstorm WarningJKLBell, Harlan18 min
Apr 9, 3:42 PM EDTTornado WarningRNKGrayson33 min
Apr 9, 3:43 PM EDTSevere Thunderstorm WarningGSPJackson, Macon62 min
Apr 9, 3:47 PM EDTSevere Thunderstorm WarningRNKAlleghany, Stokes, Surry58 min
Apr 9, 3:58 PM EDTTornado WarningGSPBurke, Cleveland, McDowell, Rutherford47 min
Apr 9, 4:00 PM EDTTornado WarningMRXHancock, Hawkins45 min
Apr 9, 4:03 PM EDTSevere Thunderstorm WarningMRXRussell, Scott, Washington, City of Bristol57 min
Apr 9, 4:15 PM EDTSevere Thunderstorm WarningRNKCarroll, Floyd, Patrick, City of Galax35 min
Apr 9, 4:18 PM EDTFlash Flood WarningRLXBoone, Lincoln, Logan4 hr
Apr 9, 4:19 PM EDTTornado WarningGSPCleveland, Gaston, Lincoln, Rutherford41 min
Apr 9, 4:20 PM EDTSevere Thunderstorm WarningMRXGreene, Sullivan, Washington40 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

Cncnati-Daytn, OH (KILN), launched 12:00Z, 4.6 hours before the alert went out and 273 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.

Skew-T log-pSkew-T log-p diagram, Cncnati-Daytn, OH at 12:00Z on 2011-04-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Cncnati-Daytn, OH at 12:00Z on 2011-04-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 257 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
589 m above ground
0-6 km bulk shear
44 kt
0-1 km storm-relative helicity
257 m²/s²
0-3 km storm-relative helicity
257 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 8, 11:07 PM EDTSevere Thunderstorm WatchSPCBreathitt, Estill, Floyd, Knott, Lee, Letcher and 6 more6 hr
Apr 9, 12:42 AM EDTMesoscale DiscussionSPCKnott, Letcher, Perry93 min
Apr 9, 7:41 AM EDTMesoscale DiscussionSPCAdair, Allen, Anderson, Barren, Bourbon, Boyle and 72 more2 hr
Apr 9, 8:25 AM EDTSevere Thunderstorm WatchSPCAdair, Allen, Anderson, Ballard, Barren, Bourbon and 72 more6 hr
Apr 9, 12:07 PM EDTMesoscale DiscussionSPCBath, Bell, Breathitt, Clark, Clay, Clinton and 25 more83 min
Apr 9, 2:00 PM EDTTornado WatchSPCBell, Boyd, Breathitt, Carter, Clay, Elliott and 27 more7 hr
Apr 8, 9:10 PM EDTMesoscale DiscussionSPCAlamance, Caswell, Chatham, Davidson, Durham, Forsyth and 11 more65 min
Apr 9, 3:23 AM EDTMesoscale DiscussionSPCAlexander, Alleghany, Ashe, Avery, Burke, Cabarrus and 19 more67 min
Apr 9, 2:44 PM EDTSevere Thunderstorm WatchSPCAlexander, Anson, Cabarrus, Catawba, Cleveland, Davie and 7 more6 hr
Apr 9, 4:21 PM EDTMesoscale DiscussionSPCAshe, Avery, Buncombe, Burke, Caldwell, Cherokee and 15 more84 min
Apr 9, 5:36 PM EDTMesoscale DiscussionSPCCleveland, Gaston, Lincoln, Mecklenburg, Polk, Rutherford and 1 more54 min
Apr 9, 6:16 PM EDTTornado WatchSPCBuncombe, Burke, Cleveland, Gaston, Haywood, Henderson and 10 more6 hr
Apr 9, 7:59 PM EDTMesoscale DiscussionSPCAnson, Buncombe, Burke, Cabarrus, Catawba, Cleveland and 13 more61 min

Nearby

Severe Thunderstorm Watches in Kentucky, 2011Severe Thunderstorm Watches in Tennessee, 2011Severe Thunderstorm Watches in North Carolina, 2011Every severe thunderstorm watch in 2011

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.