Alert archive / Wyoming / Tornado Warnings in 2010

Tornado Warning 21, NWS Cheyenne, WY

June 20, 2010Goshen County, Platte County, Wyoming

NWS Cheyenne, WY issued this tornado warning at Jun 20, 2010, 4:02 PM MDT for Goshen County, Platte County, Wyoming. It was in force for 28 min. 11 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 20, 2010, 4:02 PM MDT (22:02 UTC)
Expired
Jun 20, 2010, 4:30 PM MDT
In force
28 min
Issued by
NWS Cheyenne, WY
Area
Storm-based polygon

Counties Goshen County, WY, Platte County, WY

The radar

The Cheyenne radar (KCYS), 72 km from the middle of the area, began a volume at 22:01 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 20, 4:03 PM MDTFUNNEL CLOUD2 Sw Chugwater, WYTHE REPORT WAS 2 FUNNEL CLOUDS.
Jun 20, 4:03 PM MDTTORNADO2 Ese Chugwater, WYESPOTTER REPORT.
Jun 20, 4:04 PM MDTFUNNEL CLOUD1 Wsw Chugwater, WY
Jun 20, 4:18 PM MDTHAIL 24 E Chugwater, WY
Jun 20, 4:25 PM MDTHAIL 1.75Chugwater, WY
Jun 20, 4:25 PM MDTHAIL 4Chugwater, WY
Jun 20, 4:26 PM MDTTORNADO4 Ese Chugwater, WY
Jun 20, 4:26 PM MDTTORNADO7 E Chugwater, WY
Jun 20, 4:33 PM MDTHAIL 2.755 E Chugwater, WY
Jun 20, 4:35 PM MDTTORNADO2 S Chugwater, WYSPOTTER WAS 5 EAST OF CHUGWATER LOOKING SOUTHWEST.
Jun 20, 4:40 PM MDTHAIL 46 E Chugwater, WY

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.

IssuedProductOfficeLasted
Jun 20, 1:30 PM MDTTornado WatchSPC7 hr

The nearest sounding before it

Denver, CO (KDNR), launched 12:00Z, 10.0 hours before the alert went out and 245 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, Denver, CO at 12:00Z on 2010-06-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1555 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Denver, CO at 12:00Z on 2010-06-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 9 square meters per square second.1939587897Sfc1 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
1555 J/kg
Mixed-layer CIN
-237 J/kg
Mixed-layer LCL
1177 m above ground
0-6 km bulk shear
48 kt
0-1 km storm-relative helicity
9 m²/s²
0-3 km storm-relative helicity
159 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.8

Open this sounding in Storm Lab

The text

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

630 
WFUS55 KCYS 202202
TORCYS
WYC015-031-202230-
/O.NEW.KCYS.TO.W.0021.100620T2202Z-100620T2230Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE CHEYENNE WY
402 PM MDT SUN JUN 20 2010

THE NATIONAL WEATHER SERVICE IN CHEYENNE HAS ISSUED A

* TORNADO WARNING FOR...
  SOUTHWESTERN GOSHEN COUNTY IN SOUTHEAST WYOMING...
  SOUTHEASTERN PLATTE COUNTY IN SOUTHEAST WYOMING...

* UNTIL 430 PM MDT

* AT 401 PM MDT...TRAINED WEATHER SPOTTERS REPORTED A FUNNEL CLOUD
  NEAR CHUGWATER...OR 21 MILES SOUTH OF WHEATLAND. A TORNADO MAY
  DEVELOP AT ANY TIME. DOPPLER RADAR SHOWED THIS DANGEROUS STORM
  MOVING EAST AT 25 MPH.

* LOCATIONS IMPACTED INCLUDE...
  CHUGWATER AND I-25 EXIT 54.

THIS INCLUDES INTERSTATE 25 IN WYOMING BETWEEN MILE MARKERS 49 AND
63.

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 4187 10445 4168 10451 4167 10497 4185 10496
TIME...MOT...LOC 2202Z 270DEG 22KT 4176 10484

$$

TJT
1 follow-up statement
753 
WWUS55 KCYS 202221
SVSCYS

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE CHEYENNE WY
421 PM MDT SUN JUN 20 2010

WYC015-031-202230-
/O.CON.KCYS.TO.W.0021.000000T0000Z-100620T2230Z/
GOSHEN WY-PLATTE WY-
421 PM MDT SUN JUN 20 2010

...A TORNADO WARNING REMAINS IN EFFECT FOR SOUTHEASTERN PLATTE AND
SOUTHWESTERN GOSHEN COUNTIES UNTIL 430 PM MDT...

AT 415 PM MDT...TRAINED WEATHER SPOTTERS REPORTED A BRIEF TORNADO
TOUCHDOWN NEAR CHUGWATER.  THIS TORNADO WAS LOCATED NEAR 
CHUGWATER...OR 23 MILES SOUTHEAST OF WHEATLAND....

LOCATIONS IMPACTED INCLUDE...
  MAINLY RURAL AREAS OF EXTREME SOUTHEASTERN PLATTE AND EXTREME
  SOUTHWESTERN GOSHEN COUNTIES.

THIS INCLUDES INTERSTATE 25 IN WYOMING BETWEEN MILE MARKERS 49 AND
63.

IN ADDITION...2 INCH DIAMETER HAIL WAS REPORTED 4 MILES EAST OF
CHUGWATER.

&&

LAT...LON 4187 10445 4168 10451 4167 10497 4185 10496
TIME...MOT...LOC 2219Z 270DEG 22KT 4176 10470

$$

TJT

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 19, 6:11 PM MDTAreal Flood AdvisoryCYSNiobrara3 hr
Jun 19, 6:25 PM MDTSevere Thunderstorm WarningCYSNiobrara29 min
Jun 19, 9:21 PM MDTSevere Thunderstorm WarningCYSGoshen54 min
Jun 20, 12:05 AM MDTSevere Thunderstorm WarningCYSNiobrara25 min
Jun 20, 1:59 PM MDTSevere Thunderstorm WarningCYSGoshen, Platte35 min
Jun 20, 3:24 PM MDTSevere Thunderstorm WarningCYSGoshen, Platte51 min
Jun 20, 3:42 PM MDTSevere Thunderstorm WarningCYSNiobrara39 min
Jun 20, 3:56 PM MDTFlash Flood WarningCYSGoshen, Platte5 hr
Jun 20, 4:02 PM MDTSevere Thunderstorm WarningCYSGoshen58 min
Jun 20, 4:30 PM MDTTornado WarningCYSGoshen, Laramie, Platte30 min
Jun 20, 4:58 PM MDTTornado WarningCYSGoshen, Platte32 min
Jun 20, 5:39 PM MDTSevere Thunderstorm WarningCYSGoshen, Laramie51 min
Jun 20, 5:49 PM MDTTornado WarningCYSConverse41 min

Nearby

Tornado Warnings in Wyoming, 2010Every tornado warning in 2010Tornadoes 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.