Alert archive / Nebraska / Severe Thunderstorm Watches in 2010
Severe Thunderstorm Watch 421
The Storm Prediction Center issued this severe thunderstorm watch at Jun 27, 2010, 12:37 AM CDT for 4 counties in Iowa; 20 counties in Nebraska. It was in force for 3 hr.
The area
The outline as issued.
The facts
- Issued
- Jun 27, 2010, 12:37 AM CDT (05:37 UTC)
- Expired
- Jun 27, 2010, 3:46 AM CDT
- In force
- 3 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 2 in
- Strongest gust expected
- 60 kt
All 24 counties
Harrison County, IA, Monona County, IA, Pottawattamie County, IA, Shelby County, IA, Antelope County, NE, Boone County, NE, Burt County, NE, Butler County, NE, Cass County, NE, Colfax County, NE, Cuming County, NE, Dodge County, NE, Douglas County, NE, Lancaster County, NE, Madison County, NE, Pierce County, NE, Platte County, NE, Sarpy County, NE, Saunders County, NE, Seward County, NE, Stanton County, NE, Thurston County, NE, Washington County, NE, Wayne County, NE
The radar
The Omaha radar (KOAX), 44 km from the middle of the area, began a volume at 05:38 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
- 30%
- One or more gusts of 65 knots or more
- 30%
- 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
- 70%
Warnings issued inside it
6 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 27, 12:45 AM CDT | Severe Thunderstorm Warning | OAX | Antelope, Pierce | 45 min |
| Jun 27, 12:52 AM CDT | Flash Flood Warning | OAX | Colfax, Platte, Stanton | 3 hr |
| Jun 27, 1:17 AM CDT | Severe Thunderstorm Warning | OAX | Burt, Cuming, Thurston | 43 min |
| Jun 27, 1:35 AM CDT | Severe Thunderstorm Warning | OAX | Cuming, Stanton, Wayne | 29 min |
| Jun 27, 1:58 AM CDT | Severe Thunderstorm Warning | OAX | Thurston | 47 min |
| Jun 27, 2:10 AM CDT | Flash Flood Warning | OAX | Cuming, Thurston | 3 hr |
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, 5.6 hours before the alert went out and 44 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
- 4268 J/kg
- Mixed-layer CIN
- -78 J/kg
- Mixed-layer LCL
- 1405 m above ground
- 0-6 km bulk shear
- 16 kt
- 0-1 km storm-relative helicity
- 24 m²/s²
- 0-3 km storm-relative helicity
- 144 m²/s²
- Significant tornado parameter
- 0.8
- Supercell composite
- 10.0
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 26, 7:56 PM CDT | Severe Thunderstorm Watch | SPC | Allamakee, Audubon, Black Hawk, Boone, Bremer, Butler and 35 more | 7 hr |
| Jun 26, 9:33 PM CDT | Mesoscale Discussion | SPC | Plymouth, Woodbury | 87 min |
| Jun 26, 10:58 PM CDT | Mesoscale Discussion | SPC | Allamakee, Black Hawk, Boone, Bremer, Buchanan, Butler and 12 more | 92 min |
| Jun 26, 11:14 PM CDT | Severe Thunderstorm Watch | SPC | Benton, Buchanan, Delaware, Dubuque, Jackson, Jones and 1 more | 5 hr |
| Jun 27, 1:16 AM CDT | Mesoscale Discussion | SPC | Allamakee, Clayton, Delaware, Dubuque | 89 min |
| Jun 27, 2:06 AM CDT | Mesoscale Discussion | SPC | Adair, Adams, Audubon, Boone, Carroll, Cass and 24 more | 84 min |
| Jun 27, 2:52 AM CDT | Severe Thunderstorm Watch | SPC | Adair, Adams, Appanoose, Audubon, Benton, Boone and 35 more | 5 hr |
| Jun 27, 5:58 AM CDT | Mesoscale Discussion | SPC | Appanoose, Cedar, Clayton, Clinton, Davis, Decatur and 21 more | 92 min |
Nearby
Severe Thunderstorm Watches in Nebraska, 2010Severe Thunderstorm Watches in Iowa, 2010Every severe thunderstorm watch in 2010
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.