Alert archive / Wyoming / Tornado Warnings in 1990

Tornado Warning 8, NWS Cheyenne, WY

May 20, 1990Laramie County, Wyoming

NWS Cheyenne, WY issued this tornado warning at May 20, 1990, 1:53 PM MDT for Laramie County, Wyoming. It was in force for 37 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
May 20, 1990, 1:53 PM MDT (19:53 UTC)
Expired
May 20, 1990, 2:30 PM MDT
In force
37 min
Issued by
NWS Cheyenne, WY
Area
Whole counties

County Laramie 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

TimeReportWhereRemark
May 20, 1:55 PM MDTTornado F0Laramie, 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

Denver, CO (KDEN), launched 12:00Z, 7.9 hours before the alert went out and 202 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 1990-05-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 85 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, Denver, CO at 12:00Z on 1990-05-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 4 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
85 J/kg
Mixed-layer CIN
-310 J/kg
Mixed-layer LCL
1475 m above ground
0-6 km bulk shear
20 kt
0-1 km storm-relative helicity
4 m²/s²
0-3 km storm-relative helicity
-12 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 201954
TORCYS
WYC021-202030-
 
BULLETIN - EBS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE CHEYENNE WY
153 PM MDT SUN MAY 20 1990
 
THE NATIONAL WEATHER SERVICE IN CHEYENNE HAS ISSUED A
TORNADO WARNING EFFECTIVE UNTIL  230 PM MDT
FOR PEOPLE IN THE FOLLOWING COUNTY...
 
IN SOUTHEAST WYOMING
          ...SOUTHERN LARAMIE
 
SEVERAL FUNNEL CLOUDS WERE SPOTTTED BY TOWER PERSONNEL TO THE NORTH
OF THE AIROPRT. THE PARENT THUNDERSTORM WAS MOVING TO THE NORTHEAST
AT 20 MPH.
 
 
IF YOU ARE IN THE PATH OF A 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
SUCH AS A CLOSET ON THE LOWEST& FLOOR.  USE BLANKETS...PILLOWS...
OR CUSHIONS TO COVER YOUR BODY.  AVOID WINDOWS.
LAUZE

The office that day

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

IssuedProductOfficeCountiesLasted
May 20, 1:30 PM MDTSevere Thunderstorm WarningCYSLaramie60 min
May 20, 2:27 PM MDTSevere Thunderstorm WarningCYSGoshen63 min

Nearby

Tornado Warnings in Wyoming, 1990Every tornado warning in 1990Tornadoes in 1990

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.