Alert archive / Utah / Special Weather Statements in 2021

Special Weather Statement, NWS Salt Lake City, UT

September 11, 2021Duchesne County, Utah

NWS Salt Lake City, UT issued this special weather statement at Sep 11, 2021, 1:39 PM MDT for Duchesne County, Utah. It was in force for 51 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: Sep 11, 2021, 1:39 PM MDT (19:39 UTC)
Expired: Sep 11, 2021, 2:30 PM MDT
In force: 51 min
Issued by: NWS Salt Lake City, UT
Hail: 0.25 in
Wind: 50

County Duchesne County, UT

The radar

The Salt Lake City radar (KMTX), 210 km from the middle of the area, began a volume at 19:40 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

Elko, NV (KLKN), launched 12:00Z, 7.7 hours before the alert went out and 318 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: 1 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 1278 m above ground
0-6 km bulk shear: 40 kt
0-1 km storm-relative helicity: 46 m²/s²
0-3 km storm-relative helicity: 96 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

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What forecasters said that day

The local office's own words before this special weather statement 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 special weather statement went out at Sep 11, 3:19 AM MDT, 10 hours 20 minutes earlier.

Area forecast discussion, Sep 11, 3:19 AM MDT, 10 hours 20 minutes before

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Hazardous weather outlook, Sep 11, 3:25 AM MDT, 10 hours 14 minutes before

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In the hours before

Special weather statement, Sep 11, 12:54 PM MDT, 45 minutes before

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Special weather statement, Sep 11, 1:39 PM MDT, 0 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
Sep 10, 6:06 PM MDT	Severe Thunderstorm Warning	SLC	Box Elder, Weber	39 min
Sep 10, 6:20 PM MDT	Severe Thunderstorm Warning	SLC	Davis, Morgan, Weber	25 min
Sep 10, 6:42 PM MDT	Special Weather Statement	SLC	Morgan, Weber	33 min
Sep 10, 6:42 PM MDT	Special Weather Statement	SLC	Davis	33 min
Sep 10, 6:50 PM MDT	Severe Thunderstorm Warning	SLC	Davis, Salt Lake, Tooele	25 min
Sep 10, 7:10 PM MDT	Special Weather Statement	SLC	Salt Lake, Utah	50 min
Sep 10, 7:10 PM MDT	Severe Thunderstorm Warning	SLC	Davis, Morgan, Salt Lake, Weber	35 min
Sep 10, 7:16 PM MDT	Severe Thunderstorm Warning	SLC	Davis, Salt Lake	29 min
Sep 10, 7:24 PM MDT	Special Weather Statement	SLC	Rich	51 min
Sep 10, 7:24 PM MDT	Special Weather Statement	SLC	Cache	51 min
Sep 10, 7:38 PM MDT	Special Weather Statement	SLC	Cache, Morgan, Rich, Weber	52 min
Sep 11, 12:50 PM MDT	Flash Flood Warning Considerable damage threat	SLC	Wayne	3 hr
Sep 11, 12:54 PM MDT	Special Weather Statement	SLC	Carbon	51 min
Sep 11, 1:40 PM MDT	Flash Flood Warning Considerable damage threat	SLC	Carbon	3 hr
Sep 11, 3:17 PM MDT	Special Weather Statement	SLC	Duchesne	43 min
Sep 11, 4:25 PM MDT	Special Weather Statement	SLC	Millard	35 min
Sep 11, 5:10 PM MDT	Special Weather Statement	SLC	Juab	35 min
Sep 11, 5:19 PM MDT	Special Weather Statement	SLC	Millard	26 min
Sep 11, 5:44 PM MDT	Special Weather Statement	SLC	Millard	46 min

Nearby

Special Weather Statements in Utah, 2021 Every special weather statement in 2021

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.