Alert archive / Wyoming / Severe Thunderstorm Warnings in 1998

Severe Thunderstorm Warning 87, NWS Cheyenne, WY

July 1, 1998Converse County, Wyoming

NWS Cheyenne, WY issued this severe thunderstorm warning at Jul 1, 1998, 7:10 PM MDT for Converse County, Wyoming. It was in force for 60 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Jul 1, 1998, 7:10 PM MDT (01:10 UTC)
Expired
Jul 1, 1998, 8:10 PM MDT
In force
60 min
Issued by
NWS Cheyenne, WY
Area
Whole counties

County Converse County, WY

The radar

The Cheyenne radar (KCYS), 210 km from the middle of the area, began a volume at 01:13 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.

The nearest sounding before it

Riverton, WY (KRIW), launched 00:00Z, 1.2 hours before the alert went out and 235 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, Riverton, WY at 00:00Z on 1998-07-02Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 228 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, Riverton, WY at 00:00Z on 1998-07-02The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 29 square meters per square second.19395878Sfc1 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
228 J/kg
Mixed-layer CIN
-34 J/kg
Mixed-layer LCL
3425 m above ground
0-6 km bulk shear
32 kt
0-1 km storm-relative helicity
29 m²/s²
0-3 km storm-relative helicity
71 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.4

Open this sounding in Storm Lab

The text

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

685 
WUUS1 KCYS 020116 RRA
SVRCYS
WYC009-020210-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE CHEYENNE WY
710 PM MDT THU JUL 1 1998


THE NATIONAL WEATHER SERVICE IN CHEYENNE WYOMING HAS ISSUED A 

* SEVERE THUNDERSTORM WARNING FOR
  NORTHERN CONVERSE COUNTY IN EAST CENTRAL  WYOMING

* UNTIL 810 PM MDT

* AT 710 PM A SEVERE THUNDERSTORM WAS INDICATED BY RADAR 50  MILES
   NORTHWEST OF DOUGLAS...OR 25 MILES NORTHWEST OF BILL MOVING 
  SOUTHEAST AT 10 MPH.  THIS STORM WILL REMAIN OVER OPEN COUNTRY.

LARGE HAIL IS LIKELY WITH THIS STORM.  SEEK SHELTER INSIDE A 
STURDY BUILDING AWAY FROM ALL WINDOWS UNTIL THE STORM PASSES.

WCJIN-WYNE

SULLIVAN

The office that day

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

IssuedProductOfficeCountiesLasted
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, 5:31 PM MDTSevere Thunderstorm WarningCYSLaramie49 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.