Alert archive / Nebraska / Severe Thunderstorm Watches in 2011

Severe Thunderstorm Watch 746

August 8, 20116 counties in Colorado; 13 counties in Kansas; 25 counties in Nebraska

The Storm Prediction Center issued this severe thunderstorm watch at Aug 8, 2011, 3:52 PM MDT for 6 counties in Colorado; 13 counties in Kansas; 25 counties in Nebraska. It was in force for 6 hr.

The area

The outline as issued.

The facts

Issued
Aug 8, 2011, 3:52 PM MDT (21:52 UTC)
Expired
Aug 8, 2011, 9:43 PM MDT
In force
6 hr
Issued by
the Storm Prediction Center
Largest hail expected
2 in
Strongest gust expected
65 kt
All 44 counties

Kit Carson County, CO, Logan County, CO, Phillips County, CO, Sedgwick County, CO, Washington County, CO, Yuma County, CO, Cheyenne County, KS, Decatur County, KS, Gove County, KS, Graham County, KS, Greeley County, KS, Logan County, KS, Norton County, KS, Rawlins County, KS, Sheridan County, KS, Sherman County, KS, Thomas County, KS, Wallace County, KS, Wichita County, KS, Arthur County, NE, Box Butte County, NE, Chase County, NE, Cherry County, NE, Cheyenne County, NE, Dawes County, NE, Deuel County, NE, Dundy County, NE, Frontier County, NE, Garden County, NE, Grant County, NE, Hayes County, NE, Hitchcock County, NE, Hooker County, NE, Keith County, NE, Lincoln County, NE, Logan County, NE, McPherson County, NE, Morrill County, NE, Perkins County, NE, Red Willow County, NE, Scotts Bluff County, NE, Sheridan County, NE, Sioux County, NE, Thomas County, NE

The radar

The North Platte radar (KLNX), 166 km from the middle of the area, began a volume at 21:52 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
2%
Ten or more severe wind reports
30%
One or more gusts of 65 knots or more
20%
Ten or more severe hail reports
60%
One or more hailstones of 2 inches or more
30%
Six or more combined severe hail and wind reports
90%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Aug 8, 4:21 PM MDTSevere Thunderstorm WarningLBFKeith39 min
Aug 8, 4:27 PM MDTSevere Thunderstorm WarningGLDCheyenne, Rawlins63 min
Aug 8, 4:41 PM MDTTornado WarningGLDCheyenne, Rawlins49 min
Aug 8, 4:53 PM MDTSevere Thunderstorm WarningLBFKeith, Lincoln, Perkins52 min
Aug 8, 5:07 PM MDTSevere Thunderstorm WarningGLDSherman, Thomas53 min
Aug 8, 5:08 PM MDTSevere Thunderstorm WarningLBFCuster, Lincoln52 min
Aug 8, 5:31 PM MDTSevere Thunderstorm WarningLBFChase, Hayes, Lincoln, Perkins74 min
Aug 8, 5:46 PM MDTSevere Thunderstorm WarningLBFLincoln44 min
Aug 8, 5:49 PM MDTSevere Thunderstorm WarningGLDGove, Logan56 min
Aug 8, 5:52 PM MDTSevere Thunderstorm WarningGLDRawlins53 min
Aug 8, 5:58 PM MDTSevere Thunderstorm WarningGLDThomas19 min
Aug 8, 6:31 PM MDTSevere Thunderstorm WarningBOULogan, Phillips, Sedgwick43 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

N. Platte/Lee Bi, NE (KLBF), launched 12:00Z, 9.9 hours before the alert went out and 160 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, N. Platte/Lee Bi, NE at 12:00Z on 2011-08-08Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 426 joules per kilogram.LCLLFCEL10008507005003002001001 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, N. Platte/Lee Bi, NE at 12:00Z on 2011-08-08The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 34 square meters per square second.1939587897Sfc1 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
426 J/kg
Mixed-layer CIN
-479 J/kg
Mixed-layer LCL
1363 m above ground
0-6 km bulk shear
38 kt
0-1 km storm-relative helicity
34 m²/s²
0-3 km storm-relative helicity
133 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.3

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 8, 5:27 PM MDTMesoscale DiscussionSPCKit Carson, Logan, Phillips, Sedgwick, Yuma2 hr
Aug 7, 6:13 PM MDTMesoscale DiscussionSPCBarber, Clark, Comanche, Cowley, Edwards, Ford and 11 more3 hr
Aug 7, 6:49 PM MDTSevere Thunderstorm WatchSPCJewell, Mitchell, Osborne, Smith7 hr
Aug 7, 9:45 PM MDTMesoscale DiscussionSPCAnderson, Clay, Cloud, Coffey, Dickinson, Douglas and 28 more2 hr
Aug 7, 10:08 PM MDTSevere Thunderstorm WatchSPCAllen, Anderson, Brown, Chase, Clay, Cloud and 25 more5 hr
Aug 7, 11:46 PM MDTMesoscale DiscussionSPCAllen, Anderson, Bourbon, Cherokee, Coffey, Crawford and 7 more59 min
Aug 8, 12:09 AM MDTSevere Thunderstorm WatchSPCBourbon, Crawford, Linn, Miami3 hr
Aug 8, 5:44 PM MDTSevere Thunderstorm WatchSPCClark, Comanche, Edwards, Ellis, Finney, Ford and 18 more4 hr
Aug 7, 9:28 PM MDTMesoscale DiscussionSPCAntelope, Boone, Burt, Butler, Cass, Cedar and 30 more2 hr
Aug 8, 1:41 AM MDTMesoscale DiscussionSPCAdams, Buffalo, Butler, Cass, Clay, Fillmore and 23 more34 min
Aug 8, 2:09 PM MDTMesoscale DiscussionSPCArthur, Blaine, Box Butte, Custer, Dawes, Garden and 11 more66 min

Nearby

Severe Thunderstorm Watches in Nebraska, 2011Severe Thunderstorm Watches in Kansas, 2011Severe Thunderstorm Watches in Colorado, 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.