Alert archive / Wyoming / Tornado Warnings in 2011

Tornado Warning 16, NWS Cheyenne, WY

July 2, 2011Converse County, Platte County, Wyoming

NWS Cheyenne, WY issued this tornado warning at Jul 2, 2011, 4:22 PM MDT for Converse County, Platte County, Wyoming. It was in force for 38 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: Jul 2, 2011, 4:22 PM MDT (22:22 UTC)
Expired: Jul 2, 2011, 5:00 PM MDT
In force: 38 min
Issued by: NWS Cheyenne, WY
Area: Storm-based polygon

Counties Converse County, WY, Platte County, WY

The radar

The Cheyenne radar (KCYS), 165 km from the middle of the area, began a volume at 22:25 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.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Jul 2, 2:13 PM MDT	Tornado Watch	SPC	8 hr

The nearest sounding before it

Rapid City, SD (KUNR), launched 12:00Z, 10.4 hours before the alert went out and 231 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 829 J/kg
Mixed-layer CIN: -69 J/kg
Mixed-layer LCL: 993 m above ground
0-6 km bulk shear: 25 kt
0-1 km storm-relative helicity: -3 m²/s²
0-3 km storm-relative helicity: 41 m²/s²
Significant tornado parameter: 0.0
Supercell composite: -0.1

Open this sounding in Storm Lab

The text

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

029 
WFUS55 KCYS 022222
TORCYS
WYC009-031-022300-
/O.NEW.KCYS.TO.W.0016.110702T2222Z-110702T2300Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE CHEYENNE WY
422 PM MDT SAT JUL 2 2011

THE NATIONAL WEATHER SERVICE IN CHEYENNE HAS ISSUED A

* TORNADO WARNING FOR...
  SOUTHEASTERN CONVERSE COUNTY IN EAST CENTRAL WYOMING...
  NORTH CENTRAL PLATTE COUNTY IN SOUTHEAST WYOMING...

* UNTIL 500 PM MDT

* AT 421 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO. THIS DANGEROUS
  STORM WAS LOCATED 11 MILES NORTH OF GLENDO...OR 21 MILES EAST OF
  DOUGLAS...AND MOVING SOUTH AT 15 MPH.

* LOCATIONS IMPACTED INCLUDE...
  GLENDO.

THIS INCLUDES INTERSTATE 25 IN WYOMING BETWEEN MILE MARKERS 110 AND
117.

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 4273 10495 4266 10489 4261 10490 4261 10485
      4253 10479 4247 10505 4271 10509
TIME...MOT...LOC 2222Z 345DEG 14KT 4267 10500

$$

MAZUR

1 follow-up statement

152 
WWUS55 KCYS 022240
SVSCYS

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE CHEYENNE WY
440 PM MDT SAT JUL 2 2011

WYC009-031-022300-
/O.CON.KCYS.TO.W.0016.000000T0000Z-110702T2300Z/
CONVERSE WY-PLATTE WY-
440 PM MDT SAT JUL 2 2011

...A TORNADO WARNING REMAINS IN EFFECT FOR NORTH CENTRAL PLATTE AND
SOUTHEASTERN CONVERSE COUNTIES UNTIL 500 PM MDT...

AT 439 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO.  THIS DANGEROUS
STORM WAS LOCATED 9 MILES NORTH OF GLENDO...OR 23 MILES SOUTHEAST OF
DOUGLAS...MOVING SOUTHEAST AT 10 MPH.

LOCATIONS IMPACTED INCLUDE...
  GLENDO.

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 4248 10503 4265 10506 4269 10494 4265 10490
      4264 10489 4261 10490 4261 10488 4256 10483
      4253 10481
TIME...MOT...LOC 2241Z 327DEG 9KT 4262 10498

$$

MAZUR

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 2, 3:15 PM MDT	Severe Thunderstorm Warning	CYS	Goshen, Laramie, Platte	25 min
Jul 2, 3:50 PM MDT	Tornado Warning	CYS	Converse, Niobrara	40 min
Jul 2, 4:29 PM MDT	Severe Thunderstorm Warning	CYS	Converse, Niobrara	46 min
Jul 2, 4:42 PM MDT	Severe Thunderstorm Warning	CYS	Goshen, Niobrara, Platte	48 min
Jul 2, 5:01 PM MDT	Tornado Warning	CYS	Platte	31 min
Jul 2, 5:30 PM MDT	Severe Thunderstorm Warning	CYS	Converse, Goshen, Niobrara, Platte	45 min
Jul 2, 5:40 PM MDT	Severe Thunderstorm Warning	CYS	Niobrara	37 min

Nearby

Tornado Warnings in Wyoming, 2011 Every tornado warning in 2011 Tornadoes 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.