Alert archive / Nebraska / Severe Thunderstorm Watches in 2011

Severe Thunderstorm Watch 859

October 6, 201128 counties in Nebraska; 14 counties in South Dakota; Goshen County, Niobrara County, Weston County, Wyoming

The Storm Prediction Center issued this severe thunderstorm watch at Oct 6, 2011, 2:32 PM MDT for 28 counties in Nebraska; 14 counties in South Dakota; Goshen County, Niobrara County, Weston County, Wyoming. It was in force for 9 hr.

The area

The outline as issued.

The facts

Issued
Oct 6, 2011, 2:32 PM MDT (20:32 UTC)
Expired
Oct 7, 2011, 12:00 AM MDT
In force
9 hr
Issued by
the Storm Prediction Center
Largest hail expected
1.5 in
Strongest gust expected
65 kt
All 45 counties

Arthur County, NE, Banner County, NE, Blaine County, NE, Box Butte County, NE, Brown County, NE, Chase County, NE, Cherry County, NE, Custer County, NE, Dawes County, NE, Deuel County, NE, Frontier County, NE, Garden County, NE, Grant County, NE, Hayes County, NE, Hooker County, NE, Keith County, NE, Keya Paha County, NE, Lincoln County, NE, Logan County, NE, Loup County, NE, McPherson County, NE, Morrill County, NE, Perkins County, NE, Rock County, NE, Scotts Bluff County, NE, Sheridan County, NE, Sioux County, NE, Thomas County, NE, Bennett County, SD, Butte County, SD, Custer County, SD, Fall River County, SD, Haakon County, SD, Harding County, SD, Jackson County, SD, Lawrence County, SD, Meade County, SD, Mellette County, SD, Pennington County, SD, Perkins County, SD, Todd County, SD, Ziebach County, SD, Goshen County, WY, Niobrara County, WY, Weston County, WY

The radar

The Rapid City radar (KUDX), 125 km from the middle of the area, began a volume at 20:32 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
40%
One or more gusts of 65 knots or more
40%
Ten or more severe hail reports
60%
One or more hailstones of 2 inches or more
20%
Six or more combined severe hail and wind reports
80%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Oct 6, 2:54 PM MDTSevere Thunderstorm WarningUNRCuster51 min
Oct 6, 3:18 PM MDTTornado WarningUNRCuster27 min
Oct 6, 3:23 PM MDTSevere Thunderstorm WarningUNRPennington52 min
Oct 6, 3:44 PM MDTSevere Thunderstorm WarningUNRMeade61 min
Oct 6, 3:45 PM MDTSevere Thunderstorm WarningUNRCuster30 min
Oct 6, 4:03 PM MDTSevere Thunderstorm WarningUNR57 min
Oct 6, 4:13 PM MDTSevere Thunderstorm WarningUNRCuster, Pennington41 min
Oct 6, 5:06 PM MDTSevere Thunderstorm WarningUNRBennett, Jackson, Mellette39 min
Oct 6, 5:14 PM MDTSevere Thunderstorm WarningLBFCherry31 min
Oct 6, 5:19 PM MDTSevere Thunderstorm WarningUNRBennett, Jackson37 min
Oct 6, 5:43 PM MDTSevere Thunderstorm WarningUNRBennett, Jackson, Mellette, Todd47 min
Oct 6, 5:49 PM MDTSevere Thunderstorm WarningUNRHaakon, Jackson, Mellette56 min
Oct 6, 5:54 PM MDTSevere Thunderstorm WarningUNRMeade, Perkins, Ziebach51 min
Oct 6, 5:58 PM MDTSevere Thunderstorm WarningLBFCherry32 min
Oct 6, 6:01 PM MDTTornado WarningLBFCherry29 min
Oct 6, 6:12 PM MDTSevere Thunderstorm WarningUNRBennett, Jackson48 min
Oct 6, 6:23 PM MDTTornado WarningUNRBennett, Jackson, Mellette, Todd52 min
Oct 6, 6:37 PM MDTSevere Thunderstorm WarningLBFArthur, Keith, McPherson, Perkins38 min
Oct 6, 6:38 PM MDTSevere Thunderstorm WarningUNRPerkins, Ziebach45 min
Oct 6, 7:00 PM MDTSevere Thunderstorm WarningUNRMellette, Todd45 min
Oct 6, 7:07 PM MDTSevere Thunderstorm WarningLBFHooker, McPherson, Thomas38 min
Oct 6, 7:15 PM MDTSevere Thunderstorm WarningLBFArthur, Keith, McPherson45 min
Oct 6, 7:15 PM MDTTornado WarningUNRMellette30 min
Oct 6, 7:35 PM MDTSevere Thunderstorm WarningUNRHaakon, Jackson22 min
Oct 6, 7:40 PM MDTSevere Thunderstorm WarningLBFCherry, Hooker, Thomas50 min
Oct 6, 7:47 PM MDTSevere Thunderstorm WarningUNRButte, Lawrence58 min
Oct 6, 8:06 PM MDTSevere Thunderstorm WarningLBFCherry, Hooker39 min
Oct 6, 8:30 PM MDTSevere Thunderstorm WarningLBFCherry45 min
Oct 6, 8:34 PM MDTSevere Thunderstorm WarningUNRButte, Harding41 min
Oct 6, 9:02 PM MDTSevere Thunderstorm WarningUNRTodd, Tripp58 min
Oct 6, 9:17 PM MDTSevere Thunderstorm WarningLBFCherry, Keya Paha43 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

Rapid City, SD (KUNR), launched 12:00Z, 8.5 hours before the alert went out and 118 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, Rapid City, SD at 12:00Z on 2011-10-06Temperature 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, Rapid City, SD at 12:00Z on 2011-10-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 51 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
905 m above ground
0-6 km bulk shear
47 kt
0-1 km storm-relative helicity
51 m²/s²
0-3 km storm-relative helicity
149 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
Oct 6, 2:19 PM MDTMesoscale DiscussionSPCArthur, Banner, Box Butte, Chase, Cheyenne, Dawes and 11 more116 min
Oct 6, 4:50 PM MDTMesoscale DiscussionSPCDundy, Hitchcock, Red Willow115 min
Oct 6, 4:55 PM MDTMesoscale DiscussionSPCArthur, Box Butte, Cherry, Cheyenne, Dawes, Deuel and 11 more95 min

Nearby

Severe Thunderstorm Watches in Nebraska, 2011Severe Thunderstorm Watches in South Dakota, 2011Severe Thunderstorm Watches in Wyoming, 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.