Alert archive / Utah / Severe Thunderstorm Warnings in 1997

Severe Thunderstorm Warning 77, NWS Salt Lake City, UT

August 12, 1997Box Elder County, Davis County, Weber County, Utah

NWS Salt Lake City, UT issued this severe thunderstorm warning at Aug 12, 1997, 8:09 PM MDT for Box Elder County, Davis County, Weber County, Utah. It was in force for 61 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
Aug 12, 1997, 8:09 PM MDT (02:09 UTC)
Expired
Aug 12, 1997, 9:10 PM MDT
In force
61 min
Issued by
NWS Salt Lake City, UT
Area
Whole counties

Counties Box Elder County, UT, Davis County, UT, Weber County, UT

The radar

The Salt Lake City radar (KMTX), 7 km from the middle of the area, began a volume at 02:12 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 00:00Z, 2.2 hours before the alert went out and 66 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 00:00Z on 1997-08-13Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 375 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 00:00Z on 1997-08-13The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -36 square meters per square second.1939587897Sfc1 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
375 J/kg
Mixed-layer CIN
-76 J/kg
Mixed-layer LCL
2284 m above ground
0-6 km bulk shear
35 kt
0-1 km storm-relative helicity
-36 m²/s²
0-3 km storm-relative helicity
2 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.3

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KSLC 130213 RRA
SVRSLC
UTC003-011-057-130310-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
809 PM MDT TUE AUG 12 1997

THE NATIONAL WEATHER SERVICE IN SALT LAKE CITY UT HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL 910 PM MDT
FOR PEOPLE IN THE FOLLOWING LOCATIONS...

IN NORTHWESTERN UTAH

   ...SOUTHEASTERN BOX ELDER COUNTY
   ...DAVIS COUNTY
   ...WEBER COUNTY
 
AT 804 PM MDT...A SEVERE THUNDERSTORM WAS INDICATED BY DOPPLER
RADAR 22 MILES WEST OF OGDEN OR 4 MILES NORTH OF PROMONTORY POINT
MOVING EAST AT 15 MPH.

THIS STORM IS EXPECTED TO BE NEAR WARREN AT 9 PM.

ADDITIONAL STRONG STORMS MAY DEVELOP ALONG THE WEBER/DAVIS COUNTY
LINE NEAR OR WEST OF ROY BEFORE 830 PM.
 
SEVERE THUNDERSTORMS PRODUCE DAMAGING WIND IN EXCESS OF 58 MPH...
DESTRUCTIVE HAIL...DEADLY LIGHTNING...AND VERY HEAVY RAIN.  FOR YOUR
PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF YOUR
HOME OR BUSINESS.

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 12, 10:54 PM MDTFlash Flood WarningSLCTooele61 min
Aug 12, 10:54 PM MDTSevere Thunderstorm WarningSLCTooele61 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; radar from the NEXRAD Level II archive.