Alert archive / Utah / Severe Thunderstorm Warnings in 1998

Severe Thunderstorm Warning 66, NWS Salt Lake City, UT

July 30, 1998Davis County, Weber County, Utah

NWS Salt Lake City, UT issued this severe thunderstorm warning at Jul 30, 1998, 5:38 PM MDT for Davis County, Weber County, Utah. It was in force for 52 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
Jul 30, 1998, 5:38 PM MDT (23:38 UTC)
Expired
Jul 30, 1998, 6:30 PM MDT
In force
52 min
Issued by
NWS Salt Lake City, UT
Area
Whole counties; the outline is the Mesonet’s reconstruction

Counties Davis County, UT, Weber County, UT

The radar

The Salt Lake City radar (KMTX), 44 km from the middle of the area, began a volume at 23:37 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

Salt Lake City I, UT (KSLC), launched 12:00Z, 11.6 hours before the alert went out and 35 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, Salt Lake City I, UT at 12:00Z on 1998-07-30Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 22 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, Salt Lake City I, UT at 12:00Z on 1998-07-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 52 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
22 J/kg
Mixed-layer CIN
-357 J/kg
Mixed-layer LCL
1900 m above ground
0-6 km bulk shear
16 kt
0-1 km storm-relative helicity
52 m²/s²
0-3 km storm-relative helicity
75 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.

565 
WUUS1 KSLC 302340 RRA
SVRSLC
UTC011-057-310030-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
538 PM MDT THU JUL 30 1998

THE NATIONAL WEATHER SERVICE IN SALT LAKE CITY HAS ISSUED A

   * SEVERE THUNDERSTORM WARNING FOR...
     SOUTH CENTRAL WEBER COUNTY IN UTAH
     NORTH CENTRAL DAVIS COUNTY IN UTAH
     INCLUDING KAYSVILLE AND LAYTON

   * UNTIL 630 PM MDT

   * AT 532 PM MDT A SEVERE THUNDERSTORM WAS REPORTED 2 MILES WEST OF
     KAYSVILLE...MOVING NORTH AT 20 MILES PER HOUR.

   * SEVERE THUNDERSTORM WILL BE...
     OVER LAYTON AT 540 PM MDT
     OVER HILL AFB AT 550 PM MDT
     3 MILES EAST OF ROY AT 600 PM MDT
     7 MILES NORTHEAST OF ROY AT 615 PM MDT

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 4100 11196 4118 11188 4120 11207 4102 11206

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 29, 6:02 PM MDTSevere Thunderstorm WarningSLCBox Elder43 min
Jul 29, 7:00 PM MDTFlash Flood WarningSLCSanpete75 min
Jul 29, 7:33 PM MDTSevere Thunderstorm WarningSLCDavis, Salt Lake42 min
Jul 29, 8:06 PM MDTSevere Thunderstorm WarningSLCDavis, Morgan, Salt Lake39 min
Jul 30, 4:10 PM MDTSevere Thunderstorm WarningSLCDuchesne, Summit, Wasatch50 min
Jul 30, 4:22 PM MDTSevere Thunderstorm WarningSLCBeaver, Iron53 min
Jul 30, 4:32 PM MDTSevere Thunderstorm WarningSLCEmery43 min
Jul 30, 5:59 PM MDTSevere Thunderstorm WarningSLCWeber31 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.