Alert archive / Wyoming / Tornado Warnings in 1987

Tornado Warning 16, NWS Cheyenne, WY

July 7, 1987Platte County, Wyoming

NWS Cheyenne, WY issued this tornado warning at Jul 7, 1987, 2:01 PM MDT for Platte County, Wyoming. It was in force for 29 min. 1 report came from inside the area while it was in force.

The area

The counties it named, with what was reported inside it.

The facts

Issued: Jul 7, 1987, 2:01 PM MDT (20:01 UTC)
Expired: Jul 7, 1987, 2:30 PM MDT
In force: 29 min
Issued by: NWS Cheyenne, WY
Area: Whole counties

County Platte County, WY

The radar

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

What was reported inside it

Time	Report	Where	Remark
Jul 7, 2:10 PM MDT	Hail 1.75	Platte, WY

NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in. Storm Data before 1996 records only tornadoes, thunderstorm wind and hail.

The nearest sounding before it

Rapid City, SD (KRAP), launched 12:00Z, 8.0 hours before the alert went out and 274 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 1766 m above ground
0-6 km bulk shear: 32 kt
0-1 km storm-relative helicity: -13 m²/s²
0-3 km storm-relative helicity: 22 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 KCYS 072001
TORCYS
WYC031-072030-

BULLETIN - IMMEDIATE BROADCAST REQUESTED/EBS ACTIVATION REQUESTED 
TORNADO WARNING
NATIONAL WEATHER SERVICE CHEYENNE WY
201 PM MDT TUE JUL 7 1987

THE NATIONAL WEATHER SERVICE HAS ISSUED A TORNADO WARNING 
EFFECTIVE UNTIL 230 PM MDT FOR PEOPLE IN THE FOLLOWING COUNTY OF

SOUTHEAST WYOMING...SOUTHERN PLATTE COUNTY

THIS INCLUDES THE TOWNS OF SLATER AND CHUGWATER.

AT 2 PM RADAR INDICATED A TORNADO 10 MILES NORTHWEST OF SLATER
OR 43 MILES NORTH OF CHEYENNE.  MOVEMENT OF THE TORNADO WAS
UNKNOWN BUT THE PARENT STORM WAS MOVING SOUTHEAST AT 5 MPH.

IF YOU ARE IN THE PATH OF THIS TORNADO...THE SAFEST PLACE IS A
BASEMENT.  GET UNDER A WORKBENCH OR PIECE OF STURDY FURNITURE. IF
NO BASEMENT IS AVAILABLE...SEEK SHELTER IN AN INTERIOR ROOM ON THE
LOWEST FLOOR.  USE BLANKETS OR PILLOWS TO COVER YOUR BODY.

THIS IS A DANGEROUS STORM.  ACT QUICKLY.  IF YOU ARE IN THE PATH
OF THIS TORNADO MOVE TO A SHELTER BELOW GROUND IF AVAILABLE.
OTHERWISE...GO TO A SMALL INTERIOR ROOM ON THE LOWEST FLOOR
POSSIBLE.  AVOID WINDOWS.  ABANDON CARS AND MOBILE HOMES FOR A
REINFORCED BUILDING OR GET INTO A DITCH OR CULVERT.

LAUZE

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 6, 7:20 PM MDT	Severe Thunderstorm Warning	CYS	Goshen	25 min
Jul 7, 2:31 PM MDT	Severe Thunderstorm Warning	CYS	Laramie, Platte	59 min
Jul 7, 3:30 PM MDT	Severe Thunderstorm Warning	CYS	Goshen, Laramie, Platte	60 min
Jul 7, 4:35 PM MDT	Severe Thunderstorm Warning	CYS	Goshen, Laramie	55 min
Jul 7, 5:26 PM MDT	Severe Thunderstorm Warning	CYS	Laramie	64 min

Nearby

Tornado Warnings in Wyoming, 1987 Every tornado warning in 1987 Tornadoes 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; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive.