Alert archive / Utah / Severe Thunderstorm Warnings in 1997

Severe Thunderstorm Warning 99, NWS Salt Lake City, UT

September 6, 1997Box Elder County, Utah

NWS Salt Lake City, UT issued this severe thunderstorm warning at Sep 6, 1997, 7:15 PM MDT for Box Elder County, Utah. 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
Sep 6, 1997, 7:15 PM MDT (01:15 UTC)
Expired
Sep 6, 1997, 8:15 PM MDT
In force
60 min
Issued by
NWS Salt Lake City, UT
Area
Whole counties

County Box Elder County, UT

The nearest sounding before it

Elko, NV (KLKN), launched 00:00Z, 1.3 hours before the alert went out and 118 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, Elko, NV at 00:00Z on 1997-09-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 604 joules per kilogram.LCLEL10008507005003002001001 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, Elko, NV at 00:00Z on 1997-09-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -5 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
604 J/kg
Mixed-layer CIN
-3 J/kg
Mixed-layer LCL
2786 m above ground
0-6 km bulk shear
18 kt
0-1 km storm-relative helicity
-5 m²/s²
0-3 km storm-relative helicity
46 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.2

Open this sounding in Storm Lab

The text

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

536 
WUUS1 KSLC 070117 RRA
SVRSLC
UTC003-070215-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
715 PM MDT SAT SEP 6 1997

THE NATIONAL WEATHER SERVICE IN SALT LAKE CITY UT HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL 815 PM MDT
FOR PEOPLE IN THE FOLLOWING LOCATION...

IN NORTHWESTERN UTAH

   ...NORTHWESTERN BOX ELDER COUNTY
 
AT 711 PM MDT...A SEVERE THUNDERSTORM WAS INDICATED BY DOPPLER
RADAR IN NORTHWESTERN BOX ELDER COUNTY...72 MILES NORTHWEST OF
BRIGHAM CITY AND MOVING EASTWARD AT 25 MPH.

THIS STORM IS EXPECTED TO REMAIN IN RURAL AREAS BUT COULD AFFECT
STATE ROUTE 30 BETWEEN SNOWVILLE AND PARK VALLEY WITH IN THE NEXT
30 TO 45 MINUTES
 
THIS THUNDERSTORM MAY PRODUCE STRONG GUSTY WIND...LARGE HAIL...AND
FREQUENT LIGHTNING.  TAKE COVER WHEN THREATENING WEATHER APPROACHES.

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 6, 8:50 PM MDTFlash Flood WarningSLCGarfield, Kane55 min
Sep 6, 9:22 PM MDTSevere Thunderstorm WarningSLCBox Elder58 min
Sep 6, 9:58 PM MDTFlash Flood WarningSLCKane2 hr
Sep 6, 10:19 PM MDTSevere Thunderstorm WarningSLCBox Elder, Cache61 min
Sep 7, 2:54 AM MDTSevere Thunderstorm WarningSLCUtah41 min
Sep 7, 5:58 AM MDTSevere Thunderstorm WarningSLCBox Elder, Weber47 min
Sep 7, 7:05 AM MDTSevere Thunderstorm WarningSLCDavis, Morgan30 min

Nearby

Severe Thunderstorm Warnings in Utah, 1997Every severe thunderstorm warning in 1997

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.