Alert archive / Nebraska / Severe Thunderstorm Watches in 2012
Severe Thunderstorm Watch 518
The Storm Prediction Center issued this severe thunderstorm watch at Jul 25, 2012, 4:28 PM CDT for 8 counties in Iowa; 13 counties in Kansas; 38 counties in Nebraska. It was in force for 7 hr.
The area
The outline as issued.
The facts
- Issued
- Jul 25, 2012, 4:28 PM CDT (21:28 UTC)
- Expired
- Jul 25, 2012, 11:56 PM CDT
- In force
- 7 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 2 in
- Strongest gust expected
- 60 kt
All 59 counties
Fremont County, IA, Harrison County, IA, Mills County, IA, Monona County, IA, Montgomery County, IA, Page County, IA, Pottawattamie County, IA, Shelby County, IA, Clay County, KS, Cloud County, KS, Jewell County, KS, Marshall County, KS, Mitchell County, KS, Nemaha County, KS, Osborne County, KS, Ottawa County, KS, Phillips County, KS, Republic County, KS, Rooks County, KS, Smith County, KS, Washington County, KS, Adams County, NE, Burt County, NE, Butler County, NE, Cass County, NE, Clay County, NE, Colfax County, NE, Cuming County, NE, Dodge County, NE, Douglas County, NE, Fillmore County, NE, Franklin County, NE, Gage County, NE, Hall County, NE, Hamilton County, NE, Harlan County, NE, Jefferson County, NE, Johnson County, NE, Kearney County, NE, Lancaster County, NE, Merrick County, NE, Nance County, NE, Nemaha County, NE, Nuckolls County, NE, Otoe County, NE, Pawnee County, NE, Platte County, NE, Polk County, NE, Richardson County, NE, Saline County, NE, Sarpy County, NE, Saunders County, NE, Seward County, NE, Stanton County, NE, Thayer County, NE, Thurston County, NE, Washington County, NE, Webster County, NE, York County, NE
The radar
The Grand Island radar (KUEX), 60 km from the middle of the area, began a volume at 21:31 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
- 60%
- One or more gusts of 65 knots or more
- 50%
- Ten or more severe hail reports
- 30%
- One or more hailstones of 2 inches or more
- 20%
- Six or more combined severe hail and wind reports
- 80%
Warnings issued inside it
13 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 25, 5:36 PM CDT | Severe Thunderstorm Warning | OAX | Colfax, Dodge | 24 min |
| Jul 25, 5:39 PM CDT | Severe Thunderstorm Warning | OAX | Monona | 24 min |
| Jul 25, 6:03 PM CDT | Severe Thunderstorm Warning | GID | Mitchell | 24 min |
| Jul 25, 6:17 PM CDT | Severe Thunderstorm Warning | TOP | Nemaha | 28 min |
| Jul 25, 6:26 PM CDT | Severe Thunderstorm Warning | GID | Phillips, Rooks | 34 min |
| Jul 25, 6:33 PM CDT | Severe Thunderstorm Warning | TOP | Nemaha | 17 min |
| Jul 25, 7:10 PM CDT | Severe Thunderstorm Warning | TOP | Clay, Cloud | 35 min |
| Jul 25, 7:23 PM CDT | Severe Thunderstorm Warning | TOP | Washington | 37 min |
| Jul 25, 7:28 PM CDT | Severe Thunderstorm Warning | GID | Mitchell | 31 min |
| Jul 25, 7:45 PM CDT | Severe Thunderstorm Warning | TOP | Clay, Riley, Washington | 30 min |
| Jul 25, 9:18 PM CDT | Severe Thunderstorm Warning | GID | Thayer | 27 min |
| Jul 25, 11:19 PM CDT | Severe Thunderstorm Warning | GID | Jewell, Mitchell | 41 min |
| Jul 25, 11:54 PM CDT | Severe Thunderstorm Warning | TOP | Cloud, Republic | 24 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 12:00Z, 9.5 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
- 675 J/kg
- Mixed-layer CIN
- -402 J/kg
- Mixed-layer LCL
- 2150 m above ground
- 0-6 km bulk shear
- 14 kt
- 0-1 km storm-relative helicity
- 198 m²/s²
- 0-3 km storm-relative helicity
- 222 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.1
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 25, 5:16 PM CDT | Severe Thunderstorm Watch | SPC | Adair, Adams, Allamakee, Audubon, Black Hawk, Boone and 48 more | 8 hr |
| Jul 25, 2:52 PM CDT | Mesoscale Discussion | SPC | Decatur, Gove, Graham, Jewell, Logan, Norton and 9 more | 113 min |
| Jul 25, 4:48 PM CDT | Mesoscale Discussion | SPC | Allen, Anderson, Barber, Barton, Butler, Chase and 29 more | 117 min |
Nearby
Severe Thunderstorm Watches in Nebraska, 2012Severe Thunderstorm Watches in Kansas, 2012Severe Thunderstorm Watches in Iowa, 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.