Alert archive / Nebraska / Tornado Warnings in 2011
Tornado Warning 5, NWS Cheyenne, WY
NWS Cheyenne, WY issued this tornado warning at May 9, 2011, 7:53 PM MDT for Box Butte County, Dawes County, Sioux County, Nebraska. It was in force for 28 min. 3 reports came from inside the area while it was in force.
The area
The outline as issued, with what was reported inside it.
The facts
- Issued
- May 9, 2011, 7:53 PM MDT (01:53 UTC)
- Expired
- May 9, 2011, 8:21 PM MDT
- In force
- 28 min
- Issued by
- NWS Cheyenne, WY
- Area
- Storm-based polygon
Counties Box Butte County, NE, Dawes County, NE, Sioux County, NE
The radar
The Rapid City radar (KUDX), 181 km from the middle of the area, began a volume at 01:53 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 was reported inside it
| Time | Report | Where | Remark |
|---|---|---|---|
| May 9, 8:05 PM MDT | HAIL 0.5 | 14 Sse Crawford, NE | |
| May 9, 8:09 PM MDT | HAIL 1.75 | 10 Nw Hemingford, NE | HAIL WAS 2 MILES SOUTH OF MARSLAND ALONG HWY 2. |
| May 9, 8:09 PM MDT | HAIL 1.75 | 15 Nw Hemingford, NE | HAIL WAS 2 MILES SOUTH OF MARSLAND ALONG HWY 2. |
Local storm reports filed while the alert was in force, from inside its polygon or its counties.
The watch it was issued in
The SPC watch in force over the same counties when this warning went out.
| Issued | Product | Office | Lasted |
|---|---|---|---|
| May 9, 2:26 PM MDT | Severe Thunderstorm Watch | SPC | 7 hr |
The nearest sounding before it
Rapid City, SD (KUNR), launched 00:00Z, 1.9 hours before the alert went out and 174 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
- 231 J/kg
- Mixed-layer CIN
- -129 J/kg
- Mixed-layer LCL
- 581 m above ground
- 0-6 km bulk shear
- 46 kt
- 0-1 km storm-relative helicity
- 114 m²/s²
- 0-3 km storm-relative helicity
- 247 m²/s²
- Significant tornado parameter
- -0.0
- Supercell composite
- -0.0
The text
As transmitted, in the capitals the NWS used until 2016.
043 WFUS55 KCYS 100153 TORCYS NEC013-045-165-100230- /O.NEW.KCYS.TO.W.0005.110510T0153Z-110510T0230Z/ BULLETIN - EAS ACTIVATION REQUESTED TORNADO WARNING NATIONAL WEATHER SERVICE CHEYENNE WY 753 PM MDT MON MAY 9 2011 THE NATIONAL WEATHER SERVICE IN CHEYENNE HAS ISSUED A * TORNADO WARNING FOR... NORTHWESTERN BOX BUTTE COUNTY IN THE PANHANDLE OF NEBRASKA... SOUTHWESTERN DAWES COUNTY IN THE PANHANDLE OF NEBRASKA... EAST CENTRAL SIOUX COUNTY IN THE PANHANDLE OF NEBRASKA... * UNTIL 830 PM MDT * AT 750 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A SMALL LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING A TORNADO. THESE DANGEROUS STORMS WERE LOCATED ALONG A LINE EXTENDING FROM 14 MILES NORTHEAST OF AGATE TO 13 MILES WEST OF HEMINGFORD...AND MOVING TO THE NORTHEAST AT 35 MPH. AT THAT TIME...TWO SEPERATE TORNADOES ARE POSSIBLE. ONE IS 5 MILES SOUTHEAST OF AGATE FOSSIBLE BEDS NATIONAL MONUMENT AND THE OTHER IS 10 MILES TO THE SOUTHEAST. * LOCATIONS IMPACTED INCLUDE... MAINLY RURAL AREAS OF EXTREME EASTERN SIOUX AND NORTHWESTERN BOX BUTTE COUNTIES. PRECAUTIONARY/PREPAREDNESS ACTIONS... TAKE COVER NOW. MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF A STURDY BUILDING. AVOID WINDOWS. IF IN A MOBILE HOME...A VEHICLE OR OUTDOORS...MOVE TO THE CLOSEST SUBSTANTIAL SHELTER AND PROTECT YOURSELF FROM FLYING DEBRIS. && LAT...LON 4278 10377 4263 10299 4224 10321 4242 10365 TIME...MOT...LOC 0151Z 340DEG 30KT 4248 10353 4234 10331 $$ MSW
2 follow-up statements
307 WWUS55 KCYS 100206 SVSCYS SEVERE WEATHER STATEMENT NATIONAL WEATHER SERVICE CHEYENNE WY 806 PM MDT MON MAY 9 2011 NEC013-045-165-100230- /O.CON.KCYS.TO.W.0005.000000T0000Z-110510T0230Z/ BOX BUTTE NE-DAWES NE-SIOUX NE- 806 PM MDT MON MAY 9 2011 ...A TORNADO WARNING REMAINS IN EFFECT FOR EAST CENTRAL SIOUX... SOUTHWESTERN DAWES AND NORTHWESTERN BOX BUTTE COUNTIES UNTIL 830 PM MDT... AT 802 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING A TORNADO. THESE DANGEROUS STORMS WERE LOCATED ALONG A LINE EXTENDING FROM 10 MILES SOUTH OF CRAWFORD TO BOX BUTTE DAM...MOVING TO THE NORTHEAST AT 35 MPH. ONE TORNADIC STORM WAS ABOUT 5 MILES SOUTHEAST OF CRAWFORD AND THE OTHER WAS ABOUT 10 MILES SOUTHEAST OF CRAWFORD. LOCATIONS IMPACTED INCLUDE... MARSLAND. PRECAUTIONARY/PREPAREDNESS ACTIONS... TAKE COVER NOW. MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF A STURDY BUILDING. AVOID WINDOWS. IF IN A MOBILE HOME...A VEHICLE OR OUTDOORS...MOVE TO THE CLOSEST SUBSTANTIAL SHELTER AND PROTECT YOURSELF FROM FLYING DEBRIS. && LAT...LON 4246 10352 4278 10377 4263 10299 4231 10317 TIME...MOT...LOC 0204Z 340DEG 30KT 4252 10339 4239 10311 $$ MSW
905 WWUS55 KCYS 100221 SVSCYS SEVERE WEATHER STATEMENT NATIONAL WEATHER SERVICE CHEYENNE WY 821 PM MDT MON MAY 9 2011 NEC013-045-165-100230- /O.CAN.KCYS.TO.W.0005.000000T0000Z-110510T0230Z/ BOX BUTTE NE-DAWES NE-SIOUX NE- 821 PM MDT MON MAY 9 2011 ...THE TORNADO WARNING FOR EAST CENTRAL SIOUX...SOUTHWESTERN DAWES AND NORTHWESTERN BOX BUTTE COUNTIES IS CANCELLED... THE LINE OF STORMS WHICH PROMPTED THE WARNING HAS MOVED OUT OF THE WARNED AREA. THE WARNING WAS REPLACED BY A NEW TORNADO WARNING FOR NORTH CENTRAL BOX BUTTE AND DAWES COUNTY WHICH IS IN EFFECT UNTIL 9 PM. ADDITIONAL STRONG THUNDERSTORMS ARE STILL POSSIBLE...AND A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 9 PM. LAT...LON 4246 10352 4278 10377 4263 10299 4231 10317 TIME...MOT...LOC 0220Z 340DEG 30KT 4239 10333 4226 10305 $$ MSW
The office that day
Everything else NWS Cheyenne, WY issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 9, 6:03 PM MDT | Severe Thunderstorm Warning | CYS | Sioux | 57 min |
| May 9, 6:55 PM MDT | Tornado Warning | CYS | Dawes, Sioux | 35 min |
| May 9, 7:32 PM MDT | Tornado Warning | CYS | Dawes, Sioux | 43 min |
| May 9, 8:17 PM MDT | Tornado Warning | CYS | Box Butte, Dawes | 30 min |
Nearby
Tornado Warnings in Nebraska, 2011Every tornado warning in 2011Tornadoes 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.