Alert archive / Wyoming / Severe Thunderstorm Warnings in 1998

Severe Thunderstorm Warning 95, NWS Cheyenne, WY

July 2, 1998Laramie County, Wyoming

NWS Cheyenne, WY issued this severe thunderstorm warning at Jul 2, 1998, 5:31 PM MDT for Laramie County, Wyoming. It was in force for 49 min. 4 reports 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 2, 1998, 5:31 PM MDT (23:31 UTC)
Expired
Jul 2, 1998, 6:20 PM MDT
In force
49 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 23:30 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
Jul 2, 5:35 PM MDTHail 1Cheyenne, WYSpotters reported quarter size hail on the Terry Bison Ranch 10 miles southwest of Cheyenne.
Jul 2, 5:38 PM MDTHail 1Cheyenne, WYA storm produced quarter size hail 9 miles south of Cheyenne. The hail covered the ground and wind driven hail broke some automobile windshields.
Jul 2, 6:00 PM MDTThunderstorm Wind 61Cheyenne, WYA wind gust of 70 mph was recorded in a thunderstorm 33 miles northeast of Cheyenne.
Jul 2, 6:15 PM MDTHail 0.75Cheyenne, 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.

The nearest sounding before it

Denver, CO (KDNR), launched 12:00Z, 11.5 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 1998-07-02Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 56 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 12:00Z on 1998-07-02The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 20 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
56 J/kg
Mixed-layer CIN
-473 J/kg
Mixed-layer LCL
2148 m above ground
0-6 km bulk shear
20 kt
0-1 km storm-relative helicity
20 m²/s²
0-3 km storm-relative helicity
66 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.

295 
WUUS1 KCYS 022330 RRA
SVRCYS
WYC021-030020-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE CHEYENNE WY
531 PM MDT THU JUL 2 1998

THE NATIONAL WEATHER SERVICE IN CHEYENNE HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTHERN LARAMIE COUNTY IN SOUTHEASTERN WYOMING

* UNTIL 620 PM MDT

* AT 530 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM 5 MILES SOUTHWEST OF CHEYENNE... MOVING EAST AT
  15 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  SOUTHERN CHEYENNE THROUGH 545 PM MDT

THIS IS A DANGEROUS STORM STAY INDOORS AWAY FROM WINDOWS.

ROBINSON

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 1, 7:10 PM MDTSevere Thunderstorm WarningCYSConverse60 min
Jul 1, 7:59 PM MDTTornado WarningCYSConverse31 min
Jul 1, 8:30 PM MDTSevere Thunderstorm WarningCYSConverse60 min
Jul 1, 9:22 PM MDTFlash Flood WarningCYSConverse6 hr
Jul 1, 9:33 PM MDTSevere Thunderstorm WarningCYSConverse47 min
Jul 1, 10:01 PM MDTSevere Thunderstorm WarningCYSNiobrara44 min
Jul 2, 3:47 PM MDTTornado WarningCYSAlbany28 min
Jul 2, 3:53 PM MDTSevere Thunderstorm WarningCYSAlbany47 min
Jul 2, 4:35 PM MDTSevere Thunderstorm WarningCYSLaramie45 min
Jul 2, 4:54 PM MDTSevere Thunderstorm WarningCYSLaramie41 min
Jul 2, 5:51 PM MDTSevere Thunderstorm WarningCYSGoshen49 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.