Alert archive / Utah / Severe Thunderstorm Warnings in 2024

Severe Thunderstorm Warning 99, NWS Salt Lake City, UT

September 17, 20245 counties in Utah

NWS Salt Lake City, UT issued this severe thunderstorm warning at Sep 17, 2024, 12:13 PM MDT for 5 counties in Utah. It was in force for 32 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 17, 2024, 12:13 PM MDT (18:13 UTC)
Expired: Sep 17, 2024, 12:45 PM MDT
In force: 32 min
Issued by: NWS Salt Lake City, UT
Area: Storm-based polygon
Hail: 0.75 in
Wind: 60.0 mph

Counties Box Elder County, UT, Davis County, UT, Morgan County, UT, Salt Lake County, UT, Weber County, UT

The radar

The Salt Lake City radar (KMTX), 32 km from the middle of the area, began a volume at 18:13 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

Riverton, WY (KRIW), launched 12:00Z, 6.2 hours before the alert went out and 377 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 66 J/kg
Mixed-layer CIN: -183 J/kg
Mixed-layer LCL: 1986 m above ground
0-6 km bulk shear: 38 kt
0-1 km storm-relative helicity: 53 m²/s²
0-3 km storm-relative helicity: 41 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 17, 4:18 AM MDT, 7 hours 55 minutes earlier.

Area forecast discussion, Sep 17, 4:18 AM MDT, 7 hours 55 minutes before

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In the hours before

Special weather statement, Sep 17, 6:38 AM MDT, 5 hours 35 minutes before

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Special weather statement, Sep 17, 7:34 AM MDT, 4 hours 39 minutes before

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Special weather statement, Sep 17, 7:35 AM MDT, 4 hours 38 minutes before

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      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
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      <p id="message2">
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Special weather statement, Sep 17, 8:42 AM MDT, 3 hours 31 minutes before

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<body>
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      <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.
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Special weather statement, Sep 17, 9:10 AM MDT, 3 hours 3 minutes before

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      <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 17, 11:44 AM MDT, 29 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.
      </p>
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The office that day

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

Issued	Product	Office	Counties	Lasted
Sep 17, 6:38 AM MDT	Special Weather Statement	SLC	Tooele	52 min
Sep 17, 7:34 AM MDT	Special Weather Statement	SLC		41 min
Sep 17, 7:35 AM MDT	Special Weather Statement	SLC	Box Elder	25 min
Sep 17, 8:42 AM MDT	Special Weather Statement	SLC	Box Elder	33 min
Sep 17, 9:10 AM MDT	Special Weather Statement	SLC	Box Elder	50 min
Sep 17, 10:54 AM MDT	Red Flag Warning	SLC	Carbon, Emery, Garfield, Kane, San Juan, Washington and 1 more	10 hr
Sep 17, 11:44 AM MDT	Special Weather Statement	SLC	Davis	31 min
Sep 17, 11:50 AM MDT	Severe Thunderstorm Warning Considerable damage threat	SLC	Davis, Salt Lake, Tooele	25 min
Sep 17, 12:42 PM MDT	Special Weather Statement	SLC	Weber	48 min
Sep 17, 12:48 PM MDT	Special Weather Statement	SLC	Morgan	42 min
Sep 17, 1:05 PM MDT	Special Weather Statement	SLC	Cache	25 min
Sep 17, 1:48 PM MDT	Special Weather Statement	SLC	Cache	27 min

Nearby

Severe Thunderstorm Warnings in Utah, 2024 Every severe thunderstorm warning in 2024

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.