Alert archive / Wyoming / Tornado Warnings in 2011

Tornado Warning 7, NWS Cheyenne, WY

June 12, 2011Niobrara County, Wyoming

NWS Cheyenne, WY issued this tornado warning at Jun 12, 2011, 2:56 PM MDT for Niobrara County, Wyoming. It was in force for 34 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
Jun 12, 2011, 2:56 PM MDT (20:56 UTC)
Expired
Jun 12, 2011, 3:30 PM MDT
In force
34 min
Issued by
NWS Cheyenne, WY
Area
Storm-based polygon

County Niobrara County, WY

The radar

The Rapid City radar (KUDX), 140 km from the middle of the area, began a volume at 20:59 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

TimeReportWhereRemark
Jun 12, 2:58 PM MDTTORNADOMule Creek Junction, WY
Jun 12, 3:10 PM MDTTORNADO9 Se Mule Creek Junctio, WY
Jun 12, 3:30 PM MDTTORNADOMule Creek Junction, WY

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Rapid City, SD (KUNR), launched 12:00Z, 8.9 hours before the alert went out and 133 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, Rapid City, SD at 12:00Z on 2011-06-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 15 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Rapid City, SD at 12:00Z on 2011-06-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 18 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
15 J/kg
Mixed-layer CIN
-237 J/kg
Mixed-layer LCL
1880 m above ground
0-6 km bulk shear
28 kt
0-1 km storm-relative helicity
18 m²/s²
0-3 km storm-relative helicity
48 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

066 
WFUS55 KCYS 122056
TORCYS
WYC027-122130-
/O.NEW.KCYS.TO.W.0007.110612T2056Z-110612T2130Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE CHEYENNE WY
256 PM MDT SUN JUN 12 2011

THE NATIONAL WEATHER SERVICE IN CHEYENNE HAS ISSUED A

* TORNADO WARNING FOR...
  NORTHEASTERN NIOBRARA COUNTY IN EAST CENTRAL WYOMING...

* UNTIL 330 PM MDT

* AT 251 PM MDT...LOCAL LAW ENFORCEMENT REPORTED A TORNADO NEAR
  REDBIRD...OR 22 MILES WEST OF EDGEMONT. DOPPLER RADAR SHOWED THIS
  TORNADO MOVING EAST AT 10 MPH.

* LOCATIONS IMPACTED INCLUDE...
  MULE CREEK JUNCTION.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TO REPEAT...A TORNADO IS ON THE GROUND. 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 4349 10408 4311 10405 4308 10431 4344 10434
TIME...MOT...LOC 2056Z 257DEG 7KT 4323 10424

$$

GRIFFITH
2 follow-up statements
599 
WWUS55 KCYS 122112
SVSCYS

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE CHEYENNE WY
312 PM MDT SUN JUN 12 2011

WYC027-122130-
/O.CON.KCYS.TO.W.0007.000000T0000Z-110612T2130Z/
NIOBRARA WY-
312 PM MDT SUN JUN 12 2011

...A TORNADO WARNING REMAINS IN EFFECT FOR NORTHEASTERN NIOBRARA
COUNTY UNTIL 330 PM MDT...

AT 308 PM MDT...LOCAL LAW ENFORCEMENT REPORTED A TORNADO.  THIS 
TORNADO WAS LOCATED NEAR NORTHEAST OF REDBIRD...OR 15 MILES WEST OF 
EDGEMONT...MOVING EAST AT 10 MPH.

LOCATIONS IMPACTED INCLUDE...
  MULE CREEK JUNCTION.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TO REPEAT...A TORNADO IS ON THE GROUND. 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 4349 10408 4311 10405 4308 10431 4344 10434
TIME...MOT...LOC 2112Z 257DEG 7KT 4324 10420

$$

TJT
306 
WWUS55 KCYS 122128
SVSCYS

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE CHEYENNE WY
328 PM MDT SUN JUN 12 2011

WYC027-122137-
/O.EXP.KCYS.TO.W.0007.000000T0000Z-110612T2130Z/
NIOBRARA WY-
328 PM MDT SUN JUN 12 2011

...THE TORNADO WARNING FOR NORTHEASTERN NIOBRARA COUNTY WILL EXPIRE
AT 330 PM MDT...

THE STORM WHICH PROMPTED THE WARNING HAS MOVED OUT OF THE WARNED
AREA.

TO REPORT ANY SEVERE WEATHER THAT OCCURRED WITH THIS 
THUNDERSTORM...CONTACT YOUR NEAREST LAW ENFORCEMENT AGENCY. THEY 
WILL RELAY YOUR REPORT TO THE NATIONAL WEATHER SERVICE IN CHEYENNE.

LAT...LON 4349 10408 4311 10405 4308 10431 4344 10434
TIME...MOT...LOC 2127Z 257DEG 7KT 4325 10416

$$

TJT

The office that day

Everything else NWS Cheyenne, WY issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 12, 3:07 PM MDTTornado WarningCYSNiobrara27 min

Nearby

Tornado Warnings in Wyoming, 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.