Alert archive / Utah / Severe Thunderstorm Warnings in 1997

Severe Thunderstorm Warning 111, NWS Salt Lake City, UT

September 11, 1997Box Elder County, Utah

NWS Salt Lake City, UT issued this severe thunderstorm warning at Sep 11, 1997, 3:46 PM MDT for Box Elder County, Utah. It was in force for 44 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 11, 1997, 3:46 PM MDT (21:46 UTC)
Expired
Sep 11, 1997, 4:30 PM MDT
In force
44 min
Issued by
NWS Salt Lake City, UT
Area
Whole counties

County Box Elder County, UT

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Sep 11, 1:45 PM MDTSevere Thunderstorm WatchSPC5 hr

The nearest sounding before it

Elko, NV (KLKN), launched 12:00Z, 9.8 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 12:00Z on 1997-09-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 3 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, Elko, NV at 12:00Z on 1997-09-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -38 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
3 J/kg
Mixed-layer CIN
-296 J/kg
Mixed-layer LCL
1728 m above ground
0-6 km bulk shear
45 kt
0-1 km storm-relative helicity
-38 m²/s²
0-3 km storm-relative helicity
104 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.

000 
TTAA00 KSLC 112147 RRA
SVRSLC
UTC003-112230-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
346 PM MDT THU SEP 11 1997

THE NATIONAL WEATHER SERVICE IN SALT LAKE CITY UT HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL 430 PM MDT
FOR PEOPLE IN THE FOLLOWING LOCATIONS...

IN NORTHWESTERN UTAH

   ...NORTHEASTERN BOX ELDER COUNTY
 
AT 340 PM MDT...A PAIR OF SEVERE THUNDERSTORMS WERE INDICATED BY
DOPPLER RADAR MOVING INTO NORTHEAST BOX ELDER COUNTY. MOVEMENT
WAS TO THE NORTHEAST AT AROUND 40 MPH.  THESE STORMS WILL MOVE JUST
SOUTH OF SNOWVILLE OVER THE NEXT 30-45 MINUTES.
 
HEAVY THUNDERSTORM RAINS CAN QUICKLY FLOOD ROADS.  DO NOT ATTEMPT TO
DRIVE INTO AREAS WHERE WATER COVERS THE ROAD.

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 10, 6:40 PM MDTFlash Flood WarningSLCGarfield85 min
Sep 10, 11:14 PM MDTSevere Thunderstorm WarningSLCBox Elder61 min
Sep 11, 12:33 PM MDTFlash Flood WarningSLCKane47 min
Sep 11, 1:22 PM MDTFlash Flood WarningSLCKane58 min
Sep 11, 2:02 PM MDTSevere Thunderstorm WarningSLCBox Elder48 min
Sep 11, 2:38 PM MDTSevere Thunderstorm WarningSLCCache47 min
Sep 11, 3:01 PM MDTSevere Thunderstorm WarningSLCBox Elder49 min
Sep 11, 3:17 PM MDTSevere Thunderstorm WarningSLCKane, San Juan43 min
Sep 11, 4:16 PM MDTSevere Thunderstorm WarningSLCCache34 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.