Alert archive / Wyoming / Tornado Warnings in 1987

Tornado Warning 10, NWS Cheyenne, WY

June 18, 1987Washakie County, Wyoming

NWS Cheyenne, WY issued this tornado warning at Jun 18, 1987, 5:20 PM MDT for Washakie County, Wyoming. It was in force for 40 min.

The area

The counties it named.

The facts

Issued
Jun 18, 1987, 5:20 PM MDT (23:20 UTC)
Expired
Jun 18, 1987, 6:00 PM MDT
In force
40 min
Issued by
NWS Cheyenne, WY
Area
Whole counties

County Washakie County, WY

The radar

The WSR-88D network and its archive begin in 1991, so there is no radar volume for this alert.

The nearest sounding before it

Lander/Hunt Fiel, WY (KLND), launched 12:00Z, 11.3 hours before the alert went out and 146 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, Lander/Hunt Fiel, WY at 12:00Z on 1987-06-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 131 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Lander/Hunt Fiel, WY at 12:00Z on 1987-06-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -2 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
131 J/kg
Mixed-layer CIN
-327 J/kg
Mixed-layer LCL
1779 m above ground
0-6 km bulk shear
20 kt
0-1 km storm-relative helicity
-2 m²/s²
0-3 km storm-relative helicity
146 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.

000 
TTAA00 KSHR 182324
TORSHR
WYC043-190000-

BULLETIN - EBS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE SHERIDAN WY
520 PM MDT THU JUN 18 1987

THE NATIONAL WEATHER SERVICE HAS ISSUED A TORNADO WARNING EFFECTIVE
UNTIL 600 PM FOR PEOPLE IN THE FOLLOWING COUNTY...

IN NORTH CENTRAL WYOMING
          ...NORTHEAST WASHAKIE COUNTY

THIS WARNING INCLUDES THE TOWN OF TEN SLEEP.

A TORNADO WAS OBSERVED BETWEEN HYATTVILLE AND TEN SLEEP MOVING TO THE
SOUTHEAST.
1
THIS IS A DANGEROUS STORM SITUATION. IF YOU ARE IN THE PATH OF THIS
TORNADO...SEEK SHELTER IN A BASEMENT IF POSSIBLE. OTHERWISE SEEK
SHELTER IN THE INTERIOR ROOM OF A REINFORCED BUILDING.

$$
SHK

What forecasters said that day

The local office's own words before this tornado warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

In the hours before

Special weather statement, Jun 18, 4:56 PM MDT, 24 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE CHEYENNE WY
455 PM MDT THU JUN 18 1987

...TORNADO WATCH CONTINUES FOR EASTERN THIRD OF WYOMING UNTIL 10 PM...

AT 450 PM ONLY LIGHT TO MODERATE SHOWERS AND THUNDERSTORMS WERE NOTED
IN THE SOUTHEAST CORNER OF WYOMING.  THERE HAVE BEEN NO REPORTS OF
SEVERE WEATHER IN THE SOUTHEAST CORNER.

A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR SEVERE
THUNDERSTORMS.  LARGE HAIL...DAMAGING WINDS...DEADLY LIGHTNING AND
POSSIBLY TORNADOES WILL OCCUR WITH SEVERE THUNDERSTORMS.

REMEMBER TORNADOES CAN STRIKE WITH LITTLE ADVANCE WARNING.  PEOPLE IN
THE EASTERN THIRD OF WYOMING SHOULD KEEP AN EYE TO THE SKY THE REST OF
THE AFTERNOON AND EVENING.
COX

Nearby

Tornado Warnings in Wyoming, 1987Every tornado warning in 1987Tornadoes in 1987

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.