Alert archive / Wyoming / Severe Thunderstorm Warnings in 1990
Severe Thunderstorm Warning 110, NWS Cheyenne, WY
NWS Cheyenne, WY issued this severe thunderstorm warning at Sep 2, 1990, 2:18 PM MDT for Goshen County, Laramie County, Wyoming. It was in force for 42 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
- Sep 2, 1990, 2:18 PM MDT (20:18 UTC)
- Expired
- Sep 2, 1990, 3:00 PM MDT
- In force
- 42 min
- Issued by
- NWS Cheyenne, WY
- Area
- Whole counties
Counties Goshen County, WY, 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
| Time | Report | Where | Remark |
|---|---|---|---|
| Sep 2, 3:05 PM MDT | Hail 0.75 | Laramie, 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, 8.3 hours before the alert went out and 230 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.
- Mixed-layer CAPE
- 243 J/kg
- Mixed-layer CIN
- -228 J/kg
- Mixed-layer LCL
- 991 m above ground
- 0-6 km bulk shear
- 32 kt
- 0-1 km storm-relative helicity
- 12 m²/s²
- 0-3 km storm-relative helicity
- 73 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
000
TTAA00 KCYS 022020
SVRCYS
WYC015-021-022100-
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE CHEYENNE WY
218 PM MDT SUN SEP 2 1990
THE NATIONAL WEATHER SERVICE IN CHEYENNE HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL 300 PM MDT
FOR PEOPLE IN THE FOLLOWING COUNTIES...
IN SOUTHEAST WYOMING
...SOUTHERN GOSHEN...NORTH CENTRAL LARAMIE
THIS WARNING INCLUDES THE CITY OF LA GRANGE.
AT 215 PM MDT RADAR INDICATED A SEVERE THUNDERSTORM OVER NORTH
CENTRAL LARAMIE COUNTY...20 MILES NORTH OF CHEYENNE. THE SEVERE
STORM WAS MOVING NORTHEAST AT 20 MILES AN HOUR.
IF YOU ARE CAUGHT OUTSIDE...SEEK SHELTER FROM THE WEATHER IN A
STRONG BUILDING. DAMAGI/NG WIND...LARGE HAIL...VERY HEAVY RAIN...
AND DEADLY LIGHTNING ARE ALL POSSIBLE IN SEVERE THUNDERSTORMS.
STAY INSIDE AWAY FROM WINDOWS UNTIL THE STORM HAS PASSED.
WEILANDWhat 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, Sep 2, 1:07 PM MDT, 1 hour 11 minutes before
WYZ017-022015- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE CHEYENNE WY 110 PM MDT SUN SEP 2 1990 ...THUNDERSTORMS DEVELOP ACROSS SOUTHEAST WYOMING... AT 105 PM MDT WEATHER RADAR INDICATED A BAND OF SHOWERS AND THUNDERSTORMS ACROSS THE LARAMIE MOUNTAINS ABOUT 40 MILES WEST OF WHEATLAND. A FEW STORMS ALSO DEVELOPED BETWEEN CHEYENNE AND LARAMIE. STORMS WERE MOVING NORTHEAST AT 15 MILES AN HOUR. THE AIR MASS OVER SOUTHEAST WYOMING WILL BECOME MORE UNSTABLE THIS AFTERNOON. THIS WILL CONTINUE TO PRODUCE SCATTERED THUNDERSTORMS. SOME STORMS WILL CONTAIN SMALL HAIL...FREQUENT LIGHTNING...AND BRIEF HEAVY RAIN. IF A THUNDERSTORM APPROACHES YOUR AREA...MOVE INSIDE A REINFORCED BUILDING IMMEDIATELY. MENTZER
Special weather statement, Sep 2, 2:00 PM MDT, 18 minutes before
WYZ012-016-017-022115- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE CHEYENNE WY 200 PM MDT SUN SEP 2 1990 ...STRONG THUNDERSTORMS CONTINUE TO DEVELOP OVER SOUTHEAST WYOMING... AT 150 PM MDT STRONG THUNDERSTORMS CONTINUED TO BUILD OVER SOUTHEAST WYOMING. AT THAT TIME THE STRONGEST STORMS WERE IN A LINE FROM 15 MILES SOUTHWEST OF TORRINGTON TO ABOUT 15 MILES WEST OF CHEYENNE. THE STORMS WERE MOVING NORTHEAST AT 20 MILES AN HOUR...WHILE THE LINE ITSELF HAS MOVED ONLY SLOWLY EAST. THESE STORMS WILL LIKELY PRODUCE HEAVY RAIN...SMALL HAIL...DANGEROUS LIGHTNING AND GUSTY WINDS. SINCE THE STORMS WERE MOVING OVER ROUGHLY THE SAME AREA...SOME FLOODING OF LOW LYING AREAS AND SMALL STREAMS MAY BE POSSIBLE. UNTIL 300 PM MDT THE STORMS WILL AFFECT THE CITIES OF TORRINGTON AND HAWK SPRINGS AS WELL AS RURAL AREAS BETWEEN TORRINGTON AND WEST OF CHEYENNE. PEOPLE IN SOUTHEAST WYOMING...ESPECIALLY THOSE IN THE PATH OF THE LINE OF THUND"ERSTORMS SHOULD BE PREPARED FOR THE STORMS AND WHEN A STORM NEARS...TAKE IMMEDIATE SHELTER. WEILAND
The office that day
Everything else NWS Cheyenne, WY issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 2, 3:00 PM MDT | Severe Thunderstorm Warning | CYS | Goshen, Laramie | 30 min |
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; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive.