Alert archive / Wyoming / Severe Thunderstorm Warnings in 1998

Severe Thunderstorm Warning 21, NWS Riverton, WY

July 1, 1998Washakie County, Wyoming

NWS Riverton, WY issued this severe thunderstorm warning at Jul 1, 1998, 3:54 PM MDT for Washakie County, Wyoming. It was in force for 41 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, 3:54 PM MDT (21:54 UTC)
Expired
Jul 1, 1998, 4:35 PM MDT
In force
41 min
Issued by
NWS Riverton, WY
Area
Whole counties

County Washakie County, WY

The nearest sounding before it

Riverton, WY (KRIW), launched 12:00Z, 9.9 hours before the alert went out and 109 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 12:00Z on 1998-07-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 155 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 12:00Z on 1998-07-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 88 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
155 J/kg
Mixed-layer CIN
-230 J/kg
Mixed-layer LCL
1484 m above ground
0-6 km bulk shear
58 kt
0-1 km storm-relative helicity
88 m²/s²
0-3 km storm-relative helicity
274 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.5

Open this sounding in Storm Lab

The text

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

576 
WUUS01 KRIW 012155
SVRRIW
WYC043-012235-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE RIVERTON WY
354 PM MDT WED JUL 1 1998

THE NATIONAL WEATHER SERVICE IN RIVERTON HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  WESTERN WASHAKIE COUNTY IN NORTH CENTRAL WYOMING

* UNTIL 435 PM MDT

* AT 347 PM...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A SEVERE
  THUNDERSTORM 20 MILES WEST OF WORLAND ALONG ROAD 431 OVER OPEN
  COUNTRY...MOVING EAST-NORTHEAST 12 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  OR JUST NORTH OF WORLAND AT 430 PM

DAMAGING WINDS AND LARGE HAIL ARE LIKELY. GO INSIDE A STURDY BUILDING
AND STAY AWAY FROM WINDOWS

WCJIN-WYNW
RWM

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 30, 6:04 PM MDTSevere Thunderstorm WarningRIWHot Springs31 min
Jul 1, 2:34 PM MDTSevere Thunderstorm WarningRIWPark31 min
Jul 1, 3:00 PM MDTSevere Thunderstorm WarningRIWPark30 min
Jul 1, 3:28 PM MDTSevere Thunderstorm WarningRIWBig Horn32 min
Jul 1, 4:03 PM MDTSevere Thunderstorm WarningRIWBig Horn47 min
Jul 1, 4:17 PM MDTTornado WarningRIWBig Horn33 min
Jul 1, 4:43 PM MDTSevere Thunderstorm WarningRIWWashakie27 min
Jul 1, 5:16 PM MDTSevere Thunderstorm WarningRIWWashakie44 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.