Alert archive / Utah / Severe Thunderstorm Warnings in 2023

Severe Thunderstorm Warning 94, NWS Salt Lake City, UT

September 3, 2023Box Elder County, Tooele County, Utah

NWS Salt Lake City, UT issued this severe thunderstorm warning at Sep 3, 2023, 4:00 PM MDT for Box Elder County, Tooele County, Utah. It was in force for 45 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 3, 2023, 4:00 PM MDT (22:00 UTC)
Expired
Sep 3, 2023, 4:45 PM MDT
In force
45 min
Issued by
NWS Salt Lake City, UT
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

Counties Box Elder County, UT, Tooele County, UT

The radar

The Salt Lake City radar (KMTX), 63 km from the middle of the area, began a volume at 21:59 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 watch it was issued in

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

IssuedProductOfficeLasted
Sep 3, 1:34 PM MDTSevere Thunderstorm WatchSPC7 hr

The nearest sounding before it

Salt Lake City I, UT (KSLC), launched 12:00Z, 10.0 hours before the alert went out and 104 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 2023-09-03Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 12 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 2023-09-03The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 71 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
12 J/kg
Mixed-layer CIN
-110 J/kg
Mixed-layer LCL
1751 m above ground
0-6 km bulk shear
20 kt
0-1 km storm-relative helicity
71 m²/s²
0-3 km storm-relative helicity
86 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Salt Lake City, UT wrote its last area forecast discussion before this severe thunderstorm warning went out at Sep 3, 3:28 PM MDT, 32 minutes earlier.

Area forecast discussion, Sep 3, 3:28 PM MDT, 32 minutes before
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In the hours before

Local storm report, Sep 3, 3:14 PM MDT, 46 minutes before
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Special weather statement, Sep 3, 3:20 PM MDT, 40 minutes before
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      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
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Special weather statement, Sep 3, 3:22 PM MDT, 38 minutes before
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      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
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Local storm report, Sep 3, 3:39 PM MDT, 21 minutes before
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      <p id="message2">
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Local storm report, Sep 3, 3:40 PM MDT, 20 minutes before
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<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
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Special weather statement, Sep 3, 3:55 PM MDT, 5 minutes before
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<html lang="en">
<head>
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<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
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The office that day

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

IssuedProductOfficeCountiesLasted
Sep 2, 7:51 PM MDTFlash Flood WarningSLCKane, Washington54 min
Sep 3, 12:00 PM MDTSpecial Weather StatementSLCBox Elder45 min
Sep 3, 12:44 PM MDTSpecial Weather StatementSLCBox Elder46 min
Sep 3, 12:58 PM MDTSpecial Weather StatementSLC47 min
Sep 3, 1:13 PM MDTFlash Flood Warning Considerable damage threatSLCCarbon4 hr
Sep 3, 1:45 PM MDTSpecial Weather StatementSLC45 min
Sep 3, 2:28 PM MDTSpecial Weather StatementSLCBox Elder47 min
Sep 3, 2:31 PM MDTSpecial Weather StatementSLC44 min
Sep 3, 2:37 PM MDTSevere Thunderstorm WarningSLCTooele23 min
Sep 3, 2:56 PM MDTSevere Thunderstorm WarningSLCTooele34 min
Sep 3, 3:04 PM MDTSevere Thunderstorm WarningSLCBox Elder41 min
Sep 3, 3:05 PM MDTFlash Flood Warning Considerable damage threatSLCKane, Washington3 hr
Sep 3, 3:20 PM MDTSpecial Weather StatementSLCDavis40 min
Sep 3, 3:22 PM MDTSpecial Weather StatementSLCBox Elder38 min
Sep 3, 3:25 PM MDTSevere Thunderstorm WarningSLCBox Elder, Tooele50 min
Sep 3, 3:47 PM MDTSevere Thunderstorm WarningSLCDavis, Weber28 min
Sep 3, 3:55 PM MDTSpecial Weather StatementSLCBox Elder50 min
Sep 3, 4:12 PM MDTSevere Thunderstorm WarningSLCBox Elder48 min
Sep 3, 4:14 PM MDTSevere Thunderstorm WarningSLCBox Elder, Weber31 min
Sep 3, 4:42 PM MDTSpecial Weather StatementSLCCache48 min
Sep 3, 4:45 PM MDTSevere Thunderstorm WarningSLCBox Elder45 min
Sep 3, 4:56 PM MDTSevere Thunderstorm WarningSLCBox Elder34 min
Sep 3, 5:04 PM MDTSpecial Weather StatementSLCTooele41 min
Sep 3, 5:22 PM MDTSpecial Weather StatementSLCBox Elder38 min
Sep 3, 5:24 PM MDTSevere Thunderstorm WarningSLCCache, Rich36 min
Sep 3, 5:46 PM MDTSpecial Weather StatementSLCCache29 min
Sep 3, 5:49 PM MDTSevere Thunderstorm WarningSLCCache, Rich26 min

Nearby

Severe Thunderstorm Warnings in Utah, 2023Every severe thunderstorm warning in 2023

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.