Alert archive / Wyoming / Severe Thunderstorm Warnings in 1998

Severe Thunderstorm Warning 83, NWS Cheyenne, WY

June 30, 1998Laramie County, Wyoming

NWS Cheyenne, WY issued this severe thunderstorm warning at Jun 30, 1998, 10:44 PM MDT for Laramie County, Wyoming. It was in force for 51 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
Jun 30, 1998, 10:44 PM MDT (04:44 UTC)
Expired
Jun 30, 1998, 11:35 PM MDT
In force
51 min
Issued by
NWS Cheyenne, WY
Area
Whole counties

County Laramie County, WY

The radar

The Cheyenne radar (KCYS), 20 km from the middle of the area, began a volume at 04:48 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

What was reported inside it

TimeReportWhereRemark
Jun 30, 10:55 PM MDTThunderstorm Wind 52Cheyenne, WYA storm produced wind gusts up to 60 mph, 20 miles northeast of Cheyenne.

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.

The nearest sounding before it

Denver, CO (KDNR), launched 00:00Z, 4.7 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 1998-07-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 442 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, Denver, CO at 00:00Z on 1998-07-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 10 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
442 J/kg
Mixed-layer CIN
-126 J/kg
Mixed-layer LCL
2139 m above ground
0-6 km bulk shear
39 kt
0-1 km storm-relative helicity
10 m²/s²
0-3 km storm-relative helicity
-24 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.2

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
TTAA00 KCYS 010444 RRA
SVRCYS
WYC021-010535-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE CHEYENNE WY
1044 PM MDT TUE JUN 30 1998

THE NATIONAL WEATHER SERVICE IN CHEYENNE HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NORTH CENTRAL AND NORTHEASTERN LARAMIE COUNTY IN SOUTHEASTERN
  WYOMING
  
* UNTIL 1135 PM MDT

* AT 1037 PM...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM 20 TO 25 MILES NORTH OF CHEYENNE... MOVING EAST
  AT 25 MPH.  THIS STORM LIKELY HAS WIND GUSTS IN EXCESS OF 60 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  THIS STORM WILL REMAIN OVER OPEN COUNTRY.

THIS IS A DANGEROUS STORM! STAY INDOORS AWAY FROM WINDOWS.

WCJIN-WYSE

JAD

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 30, 9:24 PM MDT, 1 hour 20 minutes before
WYZ065-066-010400-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE CHEYENNE WY
924 PM MDT TUE JUN 30 1998

...A STRONG THUNDERSTORM WAS MOVING THROUGH EAST CENTRAL ALBANY
COUNTY AT 920 PM...

THE STORM WAS LOCATED ABOUT 15 MILES NORTH OF LARAMIE...OR JUST EAST
OF BOSLER.  IT WAS MOVING SOUTHEAST AT 25 MPH AND WILL STAY EAST OF
HIGHWAY 30 AND MISS LARAMIE.

THIS STORM WAS LIKELY PRODUCING HEAVY RAIN AND SMALL HAIL...ALONG
WITH GUSTY WINDS TO &50 MPH.  PEOPLE IN EAST CENTRAL ALBANY COUNTY
SHOULD REMAIN INDOORS UNTIL THIS STORM PASSES ON BY.

WCJIN-WYSE

JAD
Special weather statement, Jun 30, 9:24 PM MDT, 1 hour 20 minutes before
WYZ065-066-010400-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE CHEYENNE WY
924 PM MDT TUE JUN 30 1998

...A STRONG THUNDERSTORM WAS MOVING THROUGH EAST CENTRAL ALBANY
COUNTY AT 920 PM...

THE STORM WAS LOCATED ABOUT 15 MILES NORTH OF LARAMIE...OR JUST EAST
OF BOSLER.  IT WAS MOVING SOUTHEAST AT 25 MPH AND WILL STAY EAST OF
HIGHWAY 30 AND MISS LARAMIE.

THIS STORM WAS LIKELY PRODUCING HEAVY RAIN AND SMALL HAIL...ALONG
WITH GUSTY WINDS TO &50 MPH.  PEOPLE IN EAST CENTRAL ALBANY COUNTY
SHOULD REMAIN INDOORS UNTIL THIS STORM PASSES ON BY.

WCJIN-WYSE

JAD

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 30, 11:17 PM MDTSevere Thunderstorm WarningCYSLaramie53 min
Jun 30, 11:38 PM MDTTornado WarningCYSLaramie32 min

Nearby

Severe Thunderstorm Warnings in Wyoming, 1998Every severe thunderstorm warning in 1998

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; radar from the NEXRAD Level II archive.