Alert archive / Nebraska / Tornado Watches in 2011
Tornado Watch 518
The Storm Prediction Center issued this tornado watch at Jun 19, 2011, 9:49 PM CDT for 8 counties in Iowa; 52 counties in Nebraska. It was in force for 6 hr.
The area
The outline as issued.
The facts
- Issued
- Jun 19, 2011, 9:49 PM CDT (02:49 UTC)
- Expired
- Jun 20, 2011, 4:00 AM CDT
- In force
- 6 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 3 in
- Strongest gust expected
- 70 kt
All 60 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, Adams County, NE, Antelope County, NE, Boone County, NE, Buffalo County, NE, Burt County, NE, Butler County, NE, Cass County, NE, Clay County, NE, Colfax County, NE, Cuming County, NE, Dawson County, NE, Dodge County, NE, Douglas County, NE, Fillmore County, NE, Franklin County, NE, Furnas County, NE, Gage County, NE, Gosper County, NE, Greeley County, NE, Hall County, NE, Hamilton County, NE, Harlan County, NE, Howard County, NE, Jefferson County, NE, Johnson County, NE, Kearney County, NE, Lancaster County, NE, Madison County, NE, Merrick County, NE, Nance County, NE, Nemaha County, NE, Nuckolls County, NE, Otoe County, NE, Pawnee County, NE, Phelps County, NE, Pierce County, NE, Platte County, NE, Polk County, NE, Richardson County, NE, Saline County, NE, Sarpy County, NE, Saunders County, NE, Seward County, NE, Sherman County, NE, Stanton County, NE, Thayer County, NE, Thurston County, NE, Valley County, NE, Washington County, NE, Wayne County, NE, Webster County, NE, York County, NE
The radar
The Omaha radar (KOAX), 95 km from the middle of the area, began a volume at 02:52 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
- 90%
- One or more EF2 to EF5 tornadoes
- 40%
- Ten or more severe wind reports
- 95%
- One or more gusts of 65 knots or more
- 40%
- Ten or more severe hail reports
- 95%
- One or more hailstones of 2 inches or more
- 50%
- Six or more combined severe hail and wind reports
- 95%
Warnings issued inside it
43 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 19, 9:56 PM CDT | Severe Thunderstorm Warning | OAX | Fremont, Mills, Page | 49 min |
| Jun 19, 9:56 PM CDT | Tornado Warning | GID | Furnas | 34 min |
| Jun 19, 10:02 PM CDT | Severe Thunderstorm Warning | GID | Furnas, Gosper, Harlan, Phelps | 58 min |
| Jun 19, 10:12 PM CDT | Tornado Warning | OAX | Fremont, Page | 48 min |
| Jun 19, 10:29 PM CDT | Tornado Warning | GID | Furnas, Harlan | 46 min |
| Jun 19, 10:39 PM CDT | Severe Thunderstorm Warning | OAX | Fremont, Mills, Page | 51 min |
| Jun 19, 10:47 PM CDT | Flash Flood Warning | OAX | Fremont, Page | 6 hr |
| Jun 19, 10:53 PM CDT | Severe Thunderstorm Warning | GID | Franklin, Harlan, Kearney, Phelps | 67 min |
| Jun 19, 11:14 PM CDT | Tornado Warning | GID | Franklin, Harlan, Kearney, Phelps | 31 min |
| Jun 19, 11:15 PM CDT | Severe Thunderstorm Warning | GID | Greeley, Howard, Sherman, Valley | 45 min |
| Jun 19, 11:31 PM CDT | Severe Thunderstorm Warning | OAX | Fremont, Mills, Montgomery, Page | 44 min |
| Jun 19, 11:36 PM CDT | Severe Thunderstorm Warning | OAX | Lancaster, Saunders | 39 min |
| Jun 19, 11:52 PM CDT | Flash Flood Warning | OAX | Cass | 5 hr |
| Jun 19, 11:53 PM CDT | Severe Thunderstorm Warning | GID | Greeley, Howard | 52 min |
| Jun 20, 12:03 AM CDT | Severe Thunderstorm Warning | GID | Dawson | 42 min |
| Jun 20, 12:13 AM CDT | Severe Thunderstorm Warning | OAX | Douglas, Saunders | 37 min |
| Jun 20, 12:21 AM CDT | Severe Thunderstorm Warning | OAX | Butler, Colfax, Dodge, Saunders | 39 min |
| Jun 20, 12:30 AM CDT | Severe Thunderstorm Warning | OAX | Saunders | 24 min |
| Jun 20, 12:37 AM CDT | Severe Thunderstorm Warning | GID | Adams, Buffalo, Hall, Kearney | 38 min |
| Jun 20, 12:37 AM CDT | Severe Thunderstorm Warning | GID | Furnas, Gosper | 38 min |
| Jun 20, 12:39 AM CDT | Severe Thunderstorm Warning | GID | Greeley, Howard, Merrick, Nance | 51 min |
| Jun 20, 12:42 AM CDT | Severe Thunderstorm Warning | GID | Dawson | 48 min |
| Jun 20, 12:48 AM CDT | Severe Thunderstorm Warning | OAX | Dodge | 42 min |
| Jun 20, 12:52 AM CDT | Tornado Warning | GID | Furnas, Gosper | 23 min |
| Jun 20, 1:08 AM CDT | Severe Thunderstorm Warning | GID | Furnas, Gosper, Harlan, Phelps | 52 min |
| Jun 20, 1:24 AM CDT | Severe Thunderstorm Warning | GID | Merrick, Nance | 51 min |
| Jun 20, 1:29 AM CDT | Severe Thunderstorm Warning | GID | Dawson, Gosper, Phelps | 31 min |
| Jun 20, 1:33 AM CDT | Severe Thunderstorm Warning | OAX | Monona | 42 min |
| Jun 20, 1:38 AM CDT | Severe Thunderstorm Warning | OAX | Butler, Colfax, Platte | 52 min |
| Jun 20, 1:42 AM CDT | Severe Thunderstorm Warning | GID | Buffalo, Kearney, Phelps | 48 min |
| Jun 20, 1:50 AM CDT | Severe Thunderstorm Warning | OAX | Butler, Colfax, Platte | 40 min |
| Jun 20, 1:51 AM CDT | Severe Thunderstorm Warning | GID | Polk | 39 min |
| Jun 20, 1:52 AM CDT | Severe Thunderstorm Warning | OAX | Harrison | 38 min |
| Jun 20, 2:02 AM CDT | Tornado Warning | GID | Merrick, Polk | 28 min |
| Jun 20, 2:07 AM CDT | Severe Thunderstorm Warning | GID | Adams, Buffalo, Hall, Kearney | 38 min |
| Jun 20, 2:25 AM CDT | Severe Thunderstorm Warning | OAX | Butler, Colfax, Dodge, Platte, Saunders | 50 min |
| Jun 20, 2:30 AM CDT | Severe Thunderstorm Warning | GID | Greeley, Howard, Nance | 14 min |
| Jun 20, 2:49 AM CDT | Severe Thunderstorm Warning | OAX | Pottawattamie, Shelby | 41 min |
| Jun 20, 2:59 AM CDT | Severe Thunderstorm Warning | OAX | Harrison | 46 min |
| Jun 20, 3:25 AM CDT | Severe Thunderstorm Warning | GID | Hamilton, Merrick, Polk, York | 35 min |
| Jun 20, 3:27 AM CDT | Severe Thunderstorm Warning | OAX | Harrison, Shelby | 48 min |
| Jun 20, 3:55 AM CDT | Severe Thunderstorm Warning | GID | Merrick, Polk, York | 32 min |
| Jun 20, 3:55 AM CDT | Severe Thunderstorm Warning | OAX | Butler, Colfax, Platte, Seward | 50 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, 2.8 hours before the alert went out and 95 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
- 2452 J/kg
- Mixed-layer CIN
- -12 J/kg
- Mixed-layer LCL
- 1426 m above ground
- 0-6 km bulk shear
- 39 kt
- 0-1 km storm-relative helicity
- -15 m²/s²
- 0-3 km storm-relative helicity
- 106 m²/s²
- Significant tornado parameter
- 0.2
- Supercell composite
- 2.2
The text
As transmitted, in the capitals the NWS used until 2016.
453
WWUS20 KWNS 200251
SEL8
SPC WW 200251
IAZ000-NEZ000-200900-
URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 518
NWS STORM PREDICTION CENTER NORMAN OK
945 PM CDT SUN JUN 19 2011
THE NWS STORM PREDICTION CENTER HAS ISSUED A
TORNADO WATCH FOR PORTIONS OF
WESTERN IOWA
CENTRAL AND EASTERN NEBRASKA
EFFECTIVE THIS SUNDAY NIGHT AND MONDAY MORNING FROM 945 PM UNTIL
400 AM CDT.
TORNADOES...HAIL TO 3 INCHES IN DIAMETER...THUNDERSTORM WIND
GUSTS TO 80 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE
AREAS.
THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 110 STATUTE
MILES EAST AND WEST OF A LINE FROM 40 MILES NORTHWEST OF TEKAMAH
NEBRASKA TO 50 MILES WEST SOUTHWEST OF BEATRICE NEBRASKA. FOR A
COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE
UPDATE (WOUS64 KWNS WOU8).
REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR
TORNADOES AND SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH
AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR
THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS
AND POSSIBLE WARNINGS.
OTHER WATCH INFORMATION...CONTINUE...WW 513...WW 515...WW
516...WW 517...
DISCUSSION...DISCRETE SUPERCELLS IN CNTRL NEB EXPECTED TO CONTINUE
MOVING/DEVELOPING GENERALLY ENEWD...WITH OTHER STORMS EXPECTED TO
CONTINUE FORMING ALONG W-E WARM FRONT IN SE NEB/SW IA. VERY STRONG
INSTABILITY /PER 00Z TOP SOUNDING/...BACKED NEAR-SFC WINDS
RESULTING FROM DEEPENING OPF W KS LEE CYCLONE...40+ KT 1 KM SLY
FLOW...AND VERY RICH MOISTURE /850 MB DEWPOINT 20C AT TOP/ SUGGEST
GOOD CHANCE FOR LARGE HAIL AND TORNADOES...IN ADDITION TO DMGG WIND
AS CONVECTION ULTIMATELY EVOLVES INTO ONE OR TWO COMPLEX MCSS.
AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 3 INCHES. EXTREME TURBULENCE AND SURFACE
WIND GUSTS TO 70 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
600. MEAN STORM MOTION VECTOR 23030.
...CORFIDISPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 19, 9:16 PM CDT | Mesoscale Discussion | SPC | Adair, Adams, Appanoose, Audubon, Boone, Carroll and 31 more | 59 min |
| Jun 19, 11:42 PM CDT | Severe Thunderstorm Watch | SPC | Benton, Cedar, Clinton, Des Moines, Henry, Iowa and 10 more | 6 hr |
| Jun 20, 1:40 AM CDT | Mesoscale Discussion | SPC | Adair, Adams, Appanoose, Audubon, Boone, Carroll and 24 more | 35 min |
| Jun 20, 3:27 AM CDT | Mesoscale Discussion | SPC | Adair, Adams, Appanoose, Audubon, Boone, Carroll and 28 more | 33 min |
| Jun 20, 3:46 AM CDT | Severe Thunderstorm Watch | SPC | Adair, Audubon, Black Hawk, Boone, Calhoun, Carroll and 26 more | 5 hr |
| Jun 20, 4:08 AM CDT | Mesoscale Discussion | SPC | Benton, Cedar, Clinton, Davis, Des Moines, Henry and 12 more | 67 min |
| Jun 20, 7:29 AM CDT | Mesoscale Discussion | SPC | Black Hawk, Grundy, Hamilton, Hardin, Jasper, Mahaska and 6 more | 61 min |
| Jun 20, 3:08 PM CDT | Tornado Watch | SPC | Audubon, Carroll, Cass, Crawford, Fremont, Harrison and 6 more | 7 hr |
| Jun 20, 5:55 PM CDT | Mesoscale Discussion | SPC | Adair, Audubon, Boone, Calhoun, Carroll, Dallas and 15 more | 65 min |
| Jun 20, 6:17 PM CDT | Mesoscale Discussion | SPC | Fremont, Harrison, Mills, Monona, Plymouth, Woodbury | 58 min |
| Jun 20, 6:53 PM CDT | Tornado Watch | SPC | Adair, Adams, Audubon, Boone, Buena Vista, Calhoun and 41 more | 6 hr |
| Jun 19, 8:24 PM CDT | Mesoscale Discussion | SPC | Adams, Blaine, Boone, Buffalo, Chase, Clay and 35 more | 96 min |
| Jun 20, 12:45 AM CDT | Severe Thunderstorm Watch | SPC | Chase, Dundy, Frontier, Hayes, Hitchcock, Red Willow | 2 hr |
| Jun 20, 8:05 AM CDT | Mesoscale Discussion | SPC | Furnas, Red Willow | 55 min |
| Jun 20, 8:38 AM CDT | Severe Thunderstorm Watch | SPC | Adams, Buffalo, Dawson, Franklin, Frontier, Furnas and 8 more | 6 hr |
| Jun 20, 12:22 PM CDT | Mesoscale Discussion | SPC | Adams, Boone, Buffalo, Clay, Custer, Dawson and 17 more | 83 min |
| Jun 20, 1:00 PM CDT | Tornado Watch | SPC | Adams, Antelope, Boone, Buffalo, Butler, Clay and 34 more | 10 hr |
| Jun 20, 2:19 PM CDT | Mesoscale Discussion | SPC | Adams, Boone, Buffalo, Clay, Dawson, Franklin and 17 more | 86 min |
| Jun 20, 2:52 PM CDT | Mesoscale Discussion | SPC | Hayes, Hitchcock, Lincoln, Logan, Red Willow | 53 min |
| Jun 20, 3:59 PM CDT | Mesoscale Discussion | SPC | Adams, Antelope, Boone, Buffalo, Clay, Custer and 21 more | 61 min |
Nearby
Tornado Watches in Nebraska, 2011Tornado Watches in Iowa, 2011Every tornado 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.