Alert archive / Wyoming / Severe Thunderstorm Warnings in 1990

Severe Thunderstorm Warning 38, NWS Cheyenne, WY

June 9, 1990Laramie County, Wyoming

NWS Cheyenne, WY issued this severe thunderstorm warning at Jun 9, 1990, 7:01 PM MDT for Laramie County, Wyoming. It was in force for 59 min.

The area

The counties it named.

The facts

Issued
Jun 9, 1990, 7:01 PM MDT (01:01 UTC)
Expired
Jun 9, 1990, 8:00 PM MDT
In force
59 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.

The nearest sounding before it

Denver, CO (KDEN), launched 00:00Z, 1.0 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 00:00Z on 1990-06-10Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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, Denver, CO at 00:00Z on 1990-06-10The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -13 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
2364 m above ground
0-6 km bulk shear
24 kt
0-1 km storm-relative helicity
-13 m²/s²
0-3 km storm-relative helicity
64 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 100101
SVRCYS
WYC021-100200-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING 
NATIONAL WEATHER SERVICE CHEYENNE WY
701 PM MDT SAT JUN 9 1990

THE NATIONAL WEATHER SERVICE HAS ISSUED A SEVERE THUNDERSTORM 
WARNING EFFECTIVE UNTIL 800 PM MDT FOR PEOPLE IN THE FOLLOWING 
COUNTY

   IN THE SOUTHEAST PART OF WYOMING
      NORTH AND CENTRAL LARAMIE COUNTY

THIS INCLUDES THE TOWN OF HORSE CREEK.

A SEVERE THUNDERSTORM CONTINUED TO MOVE THROUGH CENTRAL LARAMIE
COUNTY. AT 700 PM MDT THE STORM WAS LOCATED ABOUT 10 MILES NORTH
OF CHEYENNE...AND CONTINUED TO MOVE NORTH AT 15 MILES AN HOUR.

THIS STORM PRODUCED GOLF BALL SIZE HAIL IN SECTIONS OF CHEYENNE.

IF YOU ARE CAUGHT OUTSIDE...SEEK SHELTER FROM THE WEATHER IN A
STRONG BUILDING.  DAMAGING WIND...LARGE HAIL...VERY HEAVY RAIN...
AND DEADLY LIGHTNING ARE ALL POSSIBLE IN SEVERE THUNDERSTORMS.
STAY INSIDE UNTIL THE STORM PASSES.

A TORNADO WATCH IS ALSO IN EFFECT FOR THE WARNED AREA.  REMEMBER...
SEVERE THUNDERSTORMS CAN AND OCCASIONALLY DO PRODUCE TORNADOES
WITH LITTLE OR NO ADVANCE WARNING.

THIS STORM HAS ALSO PRODUCED HEAVY RAIN. MINOR FLOODING CAN BE
EXPECTED WITH THE STORM.

MENTZER

What forecasters said that day

The local office's own words before this severe thunderstorm 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 9, 2:10 PM MDT, 4 hours 51 minutes before
WYZ015>017-092130-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE CHEYENNE WY
210 PM MDT SAT JUN 9 1990

...THE THREAT OF SEVERE WEATHER WILL INCREASE THIS AFTERNOON AND
EVENING...

A TORNADO WATCH HAS BEEN ISSUED FOR NORTHEAST COLORADO BUT DOES NOT
...AT THIS TIME...INCLUDE ANY AREA OF WYOMING.  HOWEVER...SEVERE
THUNDERSTORMS ARE POSSIBLE IN THE SOUTHEAST CORNER OF WYOMING LATE
THIS AFTERNOON AND EVENING.

THUNDERSTORMS ARE DEVLOPING ALONG THE LARAMIE RANGE ABOUT 20 MILES
WEST OF CHEYENNE THIS AFTERNOON AND WILL MOVE SLOWLY EAST.  AROUND
5PM TO 6PM THUNDERSTORMS HAIL AND GUSTY WINDS WILL BE POSSIBLE ALONG
I-25 BETWEEN CHEYENNE AND CHUGWATER.  CHUGWATER IS ABOUT 22 MILES
SOUTH O-F WHEATLAND.

THUNDERSTORMS...SOME POSSIBLY SEVERE...WILL CONTINUE TIL AROUND SUNSET.
PEOPLE IN SOUTHEAST WYOMING ARE URGED TO KEEP AN EYE ON THE SKY AND
KEEP UP TO DATE BY LISTENING TO THIS STATION FOR WEATHER DETAILS.

SANDERS
Special weather statement, Jun 9, 4:40 PM MDT, 2 hours 21 minutes before
WYZ013-014-092330-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE CHEYENNE WY
440 PM MDT SAT JUN 9 1990

...THUNDERSTORMS MOVE OVER SOUTHWEST WYOMING...

WIDELY SCATTERED THUNDERSTORMS MOVED OVER SOUTHWEST WYOMING THIS
AFTERNOON. AT 430 PM MDT RADAR INDICATED THUNDERSTORMS EXTENDING FROM
BIG PINEY TO ROCK SPRINGS. THE STRONGEST CELL WAS NEAR THE TOWN OF
LYMAN...ABOUT 35 MILES EAST OF EVANSTON.  STORMS WERE MOVING
NORTHEAST AT 15 MILES AN HOUR.

THUNDERSTORMS WILL CONTINUE THROUGH THE NIGHT OVER WESTERN WYOMING.
SOME STORMS MAY PRODUCE GUSTY WINDS...BRIEF HEAVY RAIN...AND FREQUENT
LIGHTNING. STAY INDOORS IF A THUNDERSTORM APPROACHES YOUR AREA.

MENTZER
Special weather statement, Jun 9, 5:32 PM MDT, 1 hour 29 minutes before
WYZ017-100030-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE CHEYENNE WY
535 PM MDT SAT JUN 9 1990

...THUNDERSTORMS WERE BUILDING IN SOUTHEAST WYOMING...

WEATHER RADAR SHOWED THAT THUNDERSTORMS WERE CONTINUING TO BUILD IN
LARAMIE COUNTY OF FAR SOUTHEAST WYOMING AT 530 PM.  NONE OF THE STORMS
AT THIS TIME WERE VERY STRONG.  HOWEVER...CONDITIONS ARE RIPE FOR THESE
STORMS TO CONTINUE GETTING STRONGER IN SOUTHEAST WYOMING THIS EVENING.

JUST ACROSS THE BORDER IN NORTHEAST COLORADO...SOME STORMS WERE QUITE
STRONG.  A TORNADO WAS SPOTTED BY THE PUBLIC AT 515 PM 5 MILES WEST
OF THE TOWN OF NUNN COLORADO...WHICH IS ABOUT 30 MILES SOUTH OF THE
CITY OF CHEYENNE.

RESIDENTS OF SOUTHEAST WYOM9ING SHOULD KEEP AN EYE TO THE SKY THIS
EVENING AS THESE STORMS CONTINUE TO DEVELOP.  IF THREATENING WEATHER
APPROACHES...GO TO A SAFE PLACE.

DASELER
Special weather statement, Jun 9, 6:11 PM MDT, 50 minutes before
WYZ017-100100-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE CHEYENNE WY
610 PM MDT SAT JUN 9 1990

...A TORNADO WATCH IS IN EFFECT UNTIL 11 PM MDT FOR ALL OF SOUTHEAST
WYOMING...

THE NATIONAL SEVERE STORMS FORECAST CENTER HAS ISSUED A TORNADO
WATCH FOR ALL OF SOUTHEAST UNTIL 11 PM MDT. A TORNADO WATCH MEANS
THAT CONDITIONS ARE FAVORABLE FOR TORNADOES TO DEVELOP.

THE FOLLOWING COUNTIES ARE INCLUDED IN THIS WATCH...LARAMIE...PLATTE
...GOShHEN...THE SOUTHERN HALF OF NIOBRARA...AND SOUTHEAST CONVERSE.

IF YOU OBSERVE A TORNADO...SEEK SHELTER INSIDE A REINFORCED STRUCTURE
IMMEDIATELY.

MENTZER
Special weather statement, Jun 9, 6:14 PM MDT, 47 minutes before
WYZ017-100100-

SPECIAL WEATHER STATEMENT...CORRECTION
NATIONAL WEATHER SERVICE CHEYENNE WY
610 PM MDT SAT JUN 9 1990

...A TORNADO WATCH IS IN EFFECT UNTIL 11 PM MDT FOR ALL OF SOUTHEAST
WYOMING...

THE NATIONAL SEVERE STORMS FORECAST CENTER HAS ISSUED A TORNADO
WATCH FOR ALL OF SOUTHEAST WYOMING UNTIL 11 PM MDT. A TORNADO WATCH
MEANS THAT CONDITIONS ARE FAVORABLE FOR TORNADOES TO DEVELOP.

THE FOLLOWING COUNTIES ARE INCLUDED IN THIS WATCH..s.LARAMIE...PLATTE
...GOSHEN...THE SOUTHERN HALF OF NIOBRARA...AND SOUTHEAST CONVERSE.

IF YOU OBSERVE A TORNADO...SEEK SHELTER INSIDE A REINFORCED STRUCTURE
IMMEDIATELY.

MENTZER

Nearby

Severe Thunderstorm Warnings in Wyoming, 1990Every severe thunderstorm warning 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; the sounding from the Mesonet's radiosonde archive.