Alert archive / Wyoming / Tornado Warnings in 1987

Tornado Warning 11, NWS Cheyenne, WY

June 19, 1987Crook County, Wyoming

NWS Cheyenne, WY issued this tornado warning at Jun 19, 1987, 6:15 PM MDT for Crook County, Wyoming. It was in force for 45 min.

The area

The counties it named.

The facts

Issued
Jun 19, 1987, 6:15 PM MDT (00:15 UTC)
Expired
Jun 19, 1987, 7:00 PM MDT
In force
45 min
Issued by
NWS Cheyenne, WY
Area
Whole counties

County Crook 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

Rapid City, SD (KRAP), launched 00:00Z, 0.3 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, Rapid City, SD at 00:00Z on 1987-06-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 826 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Rapid City, SD at 00:00Z on 1987-06-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 36 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
826 J/kg
Mixed-layer CIN
-27 J/kg
Mixed-layer LCL
1230 m above ground
0-6 km bulk shear
37 kt
0-1 km storm-relative helicity
36 m²/s²
0-3 km storm-relative helicity
42 m²/s²
Significant tornado parameter
0.2
Supercell composite
2.4

Open this sounding in Storm Lab

The text

The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.

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 19, 4:01 PM MDT, 2 hours 14 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE CHEYENNE WY
400 PM MDT FRI JUN 19 1987

...STRONG THUNDERSTORM IN NORTHWEST PLATTE COUNTY...

AT 355PM A STRONG THUNDERSTORM WAS IN NORTHWEST PLATTE COUNTY...ABOUT
20 MILES NORTHWEST OF WHEATLAND.  THIS WAS 40 MILES SOUTH OF DOUGLAS
OF THE SOUTHEAST CORNER OF WYOMING.

MOVEMENT WAS TOWARD THE NORTHEAST AT 15 MILES AN HOUR.  THE STORM
SHOULD MOVE BETWEEN GLENDO AND WENDOVER BETWEEN 430 AND 5PVM.

STRONG GUSTY WINDS...HEAVY RAIN...HAIL AND INTENSE LIGHTNING SHOULD
BE EXPECTED WITH THIS STORM.
COX
Special weather statement, Jun 19, 5:25 PM MDT, 50 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE CHEYENNE WY
525 PM MDT FRI JUN 19 1987

...SEVERE THUNDERSTORM WATCH DROPPED FOR NORTH CENTRAL AND EAST
   CENTRAL WYOMING...

THE SEVERE THUNDERSTORM WATCH WAS DROPPED FROM NORTH CENTRAL AND EAST
CENTRAL WYOMING AT 515PM.

THE SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 8PM FOR THE
NORTHEAST CORNER OF WYOMING...CAMPBELL...CROOK AND WESTON COUNTIES.

PEOPLE IN THE NORTHEAST CORNER SHOULD KEEP AN EYE TO THE SKY FOR
POSSIBLE SEVERE THUNDERSTORMS UNTIL MID EVENING.
COX

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 19, 7:28 PM MDTSevere Thunderstorm WarningCYSLaramie, Platte62 min
Jun 20, 2:39 PM MDTTornado WarningCYSLaramie36 min

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.