Alert archive / Utah / Severe Thunderstorm Warnings in 1998

Severe Thunderstorm Warning 72, NWS Salt Lake City, UT

August 22, 1998Duchesne County, Utah

NWS Salt Lake City, UT issued this severe thunderstorm warning at Aug 22, 1998, 1:23 PM MDT for Duchesne County, Utah. It was in force for 37 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline the Iowa Environmental Mesonet reconstructed for it; the warning itself named whole counties.

The facts

Issued
Aug 22, 1998, 1:23 PM MDT (19:23 UTC)
Expired
Aug 22, 1998, 2:00 PM MDT
In force
37 min
Issued by
NWS Salt Lake City, UT
Area
Whole counties; the outline is the Mesonet’s reconstruction

County Duchesne County, UT

The radar

The Grand Junction radar (KGJX), 196 km from the middle of the area, began a volume at 19:26 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

Grand Junction, CO (KGJT), launched 12:00Z, 7.4 hours before the alert went out and 171 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, Grand Junction, CO at 12:00Z on 1998-08-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 60 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, Grand Junction, CO at 12:00Z on 1998-08-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 30 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
60 J/kg
Mixed-layer CIN
-199 J/kg
Mixed-layer LCL
1499 m above ground
0-6 km bulk shear
32 kt
0-1 km storm-relative helicity
30 m²/s²
0-3 km storm-relative helicity
36 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

Open this sounding in Storm Lab

The text

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

010 
WUUS1 KSLC 221926 RRA
SVRSLC
UTC013-222000-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
123 PM MDT SAT AUG 22 1998

THE NATIONAL WEATHER SERVICE IN SALT LAKE CITY HAS ISSUED A

   * SEVERE THUNDERSTORM WARNING FOR...
     SOUTHEASTERN DUCHESNE COUNTY IN UTAH

   * UNTIL 200 PM MDT

   * AT 117 PM MDT NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
     SEVERE THUNDERSTORM OVER SOUTHEASTERN DUCHESNE COUNTY...OR ABOUT
     15 MILES SOUTH OF MYTON...MOVING EAST AT 20 MILES PER HOUR.

VERY LARGE HAIL IS POSSIBLE WITH THIS SEVERE THUNDERSTORM.  THE 
STORM IS OVER RURAL AREAS BUT COULD AFFECT THE NINE MILE CANYON ROAD.

REPORT SEVERE WEATHER TO THE NEAREST LAW ENFORCEMENT AGENCY. THEY
WILL RELAY YOUR REPORT TO THE NATIONAL WEATHER SERVICE FORECAST
OFFICE IN SALT LAKE CITY.

LAT...LON 4008 11024 3981 11035 3982 10995 4022 10997

The office that day

Everything else NWS Salt Lake City, UT issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 21, 6:12 PM MDTFlash Flood WarningSLCEmery78 min
Aug 21, 8:39 PM MDTFlash Flood WarningSLCSan Juan66 min
Aug 21, 9:48 PM MDTFlash Flood WarningSLCSan Juan57 min
Aug 22, 1:30 PM MDTFlash Flood WarningSLCDuchesne60 min

Nearby

Severe Thunderstorm Warnings in Utah, 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.