Alert archive / Nebraska / Severe Thunderstorm Watches in 2012

Severe Thunderstorm Watch 254

May 5, 20124 states

The Storm Prediction Center issued this severe thunderstorm watch at May 5, 2012, 10:03 PM CDT for 4 states. It was in force for 7 hr.

The area

The outline as issued.

The facts

Issued
May 5, 2012, 10:03 PM CDT (03:03 UTC)
Expired
May 6, 2012, 4:37 AM CDT
In force
7 hr
Issued by
the Storm Prediction Center
Largest hail expected
2 in
Strongest gust expected
60 kt
All 62 counties

Buena Vista County, IA, Cherokee County, IA, Clay County, IA, Dickinson County, IA, Ida County, IA, Lyon County, IA, Monona County, IA, O'Brien County, IA, Osceola County, IA, Plymouth County, IA, Sioux County, IA, Woodbury County, IA, Cottonwood County, MN, Jackson County, MN, Lyon County, MN, Murray County, MN, Nobles County, MN, Adams County, NE, Antelope County, NE, Boone County, NE, Buffalo County, NE, Burt County, NE, Butler County, NE, Cedar County, NE, Colfax County, NE, Cuming County, NE, Custer County, NE, Dakota County, NE, Dawson County, NE, Dixon County, NE, Dodge County, NE, Frontier County, NE, Garfield County, NE, Gosper County, NE, Greeley County, NE, Hall County, NE, Hamilton County, NE, Holt County, NE, Howard County, NE, Kearney County, NE, Knox County, NE, Lincoln County, NE, Loup County, NE, Madison County, NE, Merrick County, NE, Nance County, NE, Phelps County, NE, Pierce County, NE, Platte County, NE, Polk County, NE, Sherman County, NE, Stanton County, NE, Thurston County, NE, Valley County, NE, Wayne County, NE, Wheeler County, NE, Bon Homme County, SD, Clay County, SD, Lincoln County, SD, Turner County, SD, Union County, SD, Yankton County, SD

The radar

The North Platte radar (KLNX), 179 km from the middle of the area, began a volume at 03:03 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
40%
One or more gusts of 65 knots or more
30%
Ten or more severe hail reports
60%
One or more hailstones of 2 inches or more
40%
Six or more combined severe hail and wind reports
80%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
May 5, 10:06 PM CDTSevere Thunderstorm WarningLBFBlaine, Custer, Logan39 min
May 5, 10:07 PM CDTSevere Thunderstorm WarningFSDLincoln, Lyon38 min
May 5, 10:10 PM CDTSevere Thunderstorm WarningLBFBlaine, Brown, Holt, Loup, Rock50 min
May 5, 10:24 PM CDTSevere Thunderstorm WarningLBFLincoln51 min
May 5, 10:28 PM CDTSevere Thunderstorm WarningFSDLincoln, Lyon, Murray, Nobles, Pipestone, Rock62 min
May 5, 10:28 PM CDTSevere Thunderstorm WarningLBFBlaine, Custer, Loup47 min
May 5, 10:30 PM CDTSevere Thunderstorm WarningLBFBrown, Holt, Rock60 min
May 5, 10:43 PM CDTSevere Thunderstorm WarningLBFLincoln, Logan47 min
May 5, 10:57 PM CDTSevere Thunderstorm WarningLBFHolt, Loup, Rock48 min
May 5, 11:02 PM CDTSevere Thunderstorm WarningLBFBlaine, Brown, Loup, Rock29 min
May 5, 11:19 PM CDTSevere Thunderstorm WarningLBFLincoln41 min
May 5, 11:25 PM CDTSevere Thunderstorm WarningFSDLincoln, Lyon, Murray, Pipestone65 min
May 5, 11:28 PM CDTSevere Thunderstorm WarningLBFCuster, Logan47 min
May 5, 11:29 PM CDTSevere Thunderstorm WarningLBFHolt46 min
May 6, 12:01 AM CDTFlash Flood WarningFSDLincoln, Lyon, Murray, Pipestone4 hr
May 6, 12:10 AM CDTSevere Thunderstorm WarningLBFCuster50 min
May 6, 12:28 AM CDTSevere Thunderstorm WarningFSDMurray, Pipestone47 min
May 6, 12:59 AM CDTSevere Thunderstorm WarningLBFCuster, Loup31 min
May 6, 1:01 AM CDTSevere Thunderstorm WarningGIDValley44 min
May 6, 1:43 AM CDTSevere Thunderstorm WarningGIDGreeley, Howard, Sherman, Valley47 min
May 6, 1:55 AM CDTSevere Thunderstorm WarningFSDPlymouth, Sioux35 min
May 6, 3:27 AM CDTSevere Thunderstorm WarningFSDClay20 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

Omaha, NE (KOAX), launched 00:00Z, 3.1 hours before the alert went out and 185 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, Omaha, NE at 00:00Z on 2012-05-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2892 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, Omaha, NE at 00:00Z on 2012-05-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 42 square meters per square second.193958Sfc1 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
2892 J/kg
Mixed-layer CIN
-51 J/kg
Mixed-layer LCL
1936 m above ground
0-6 km bulk shear
26 kt
0-1 km storm-relative helicity
42 m²/s²
0-3 km storm-relative helicity
89 m²/s²
Significant tornado parameter
0.1
Supercell composite
6.4

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 5, 11:31 PM CDTMesoscale DiscussionSPCLyon89 min
May 6, 2:12 AM CDTMesoscale DiscussionSPCBuena Vista, Butler, Cerro Gordo, Cherokee, Clay, Dickinson and 17 more63 min
May 6, 4:55 AM CDTMesoscale DiscussionSPCAdair, Adams, Audubon, Cass, Fremont, Guthrie and 8 more2 hr
May 6, 7:17 AM CDTSevere Thunderstorm WatchSPCAdair, Adams, Appanoose, Clarke, Dallas, Davis and 16 more6 hr
May 6, 8:40 AM CDTMesoscale DiscussionSPCCedar, Clinton, Des Moines, Henry, Iowa, Jefferson and 9 more65 min
May 6, 9:29 AM CDTSevere Thunderstorm WatchSPCBenton, Cedar, Clinton, Des Moines, Henry, Iowa and 12 more4 hr
May 6, 1:42 PM CDTSevere Thunderstorm WatchSPCDes Moines, Henry, Lee, Louisa, Van Buren7 hr
May 6, 3:56 PM CDTMesoscale DiscussionSPCLee64 min
May 5, 8:18 PM CDTSevere Thunderstorm WatchSPCBig Stone, Chippewa, Lac qui Parle, Pope, Stevens, Swift and 2 more4 hr
May 5, 9:51 PM CDTMesoscale DiscussionSPCAnoka, Benton, Big Stone, Blue Earth, Brown, Carver and 29 more84 min

Nearby

Severe Thunderstorm Watches in Nebraska, 2012Severe Thunderstorm Watches in Iowa, 2012Severe Thunderstorm Watches in South Dakota, 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.