Alert archive / Utah / Severe Thunderstorm Warnings in 2023

Severe Thunderstorm Warning 78, NWS Salt Lake City, UT

August 17, 2023Davis County, Salt Lake County, Tooele County, Utah

NWS Salt Lake City, UT issued this severe thunderstorm warning at Aug 17, 2023, 5:15 PM MDT for Davis County, Salt Lake County, Tooele County, Utah. It was in force for 16 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 17, 2023, 5:15 PM MDT (23:15 UTC)
Expired: Aug 17, 2023, 5:31 PM MDT
In force: 16 min
Issued by: NWS Salt Lake City, UT
Area: Storm-based polygon
Hail: 0.75 in
Wind: 60.0 mph

Counties Davis County, UT, Salt Lake County, UT, Tooele County, UT

The radar

The Salt Lake City radar (KMTX), 62 km from the middle of the area, began a volume at 23:16 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 12:00Z, 11.3 hours before the alert went out and 42 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: 214 J/kg
Mixed-layer CIN: -221 J/kg
Mixed-layer LCL: 2434 m above ground
0-6 km bulk shear: 3 kt
0-1 km storm-relative helicity: -3 m²/s²
0-3 km storm-relative helicity: 12 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 Aug 17, 4:10 PM MDT, 1 hour 5 minutes earlier.

Area forecast discussion, Aug 17, 4:10 PM MDT, 1 hour 5 minutes before

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In the hours before

Special weather statement, Aug 17, 3:38 PM MDT, 1 hour 37 minutes before

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Local storm report, Aug 17, 3:42 PM MDT, 1 hour 33 minutes before

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Local storm report, Aug 17, 3:49 PM MDT, 1 hour 26 minutes before

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Local storm report, Aug 17, 3:57 PM MDT, 1 hour 18 minutes before

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Special weather statement, Aug 17, 4:33 PM MDT, 42 minutes before

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Special weather statement, Aug 17, 5:07 PM MDT, 8 minutes before

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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
Aug 17, 11:35 AM MDT	Flood Watch	SLC	Beaver, Emery, Garfield, Iron, Juab, Kane and 7 more	6 days
Aug 17, 12:14 PM MDT	Flash Flood Warning Considerable damage threat	SLC	Garfield	4 hr
Aug 17, 1:24 PM MDT	Flash Flood Warning Considerable damage threat	SLC	Garfield, Wayne	3 hr
Aug 17, 1:58 PM MDT	Flash Flood Warning Considerable damage threat	SLC	Kane, Washington	3 hr
Aug 17, 2:06 PM MDT	Flash Flood Warning Considerable damage threat	SLC	Duchesne, Wasatch	4 hr
Aug 17, 2:54 PM MDT	Areal Flood Advisory	SLC	Iron	14 min
Aug 17, 3:08 PM MDT	Flash Flood Warning Considerable damage threat	SLC	Iron	112 min
Aug 17, 3:09 PM MDT	Special Weather Statement	SLC	Utah	36 min
Aug 17, 3:11 PM MDT	Special Weather Statement	SLC	Salt Lake	34 min
Aug 17, 3:19 PM MDT	Severe Thunderstorm Warning	SLC	Davis, Morgan, Salt Lake	41 min
Aug 17, 3:38 PM MDT	Special Weather Statement	SLC	Utah	52 min
Aug 17, 3:44 PM MDT	Severe Thunderstorm Warning	SLC	Utah	34 min
Aug 17, 4:33 PM MDT	Special Weather Statement	SLC	Salt Lake	42 min
Aug 17, 5:07 PM MDT	Special Weather Statement	SLC	Salt Lake	38 min

Nearby

Severe Thunderstorm Warnings in Utah, 2023 Every 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.