Alert archive / Utah / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 72, NWS Salt Lake City, UT

August 17, 2021Tooele County, Utah

NWS Salt Lake City, UT issued this severe thunderstorm warning at Aug 17, 2021, 4:29 PM MDT for Tooele County, Utah. It was in force for 46 min. 3 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Aug 17, 2021, 4:29 PM MDT (22:29 UTC)
Expired
Aug 17, 2021, 5:15 PM MDT
In force
46 min
Issued by
NWS Salt Lake City, UT
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

County Tooele County, UT

The radar

The Salt Lake City radar (KMTX), 147 km from the middle of the area, began a volume at 22:31 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.

What was reported inside it

TimeReportWhereRemark
Aug 17, 4:55 PM MDTTSTM WND GST 6225 W Dugway, UT
Aug 17, 5:15 PM MDTTSTM WND GST 6116 Wnw Dugway, UT
Aug 17, 5:15 PM MDTTSTM WND GST 6212 W Dugway, UT

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Elko, NV (KLKN), launched 12:00Z, 10.5 hours before the alert went out and 117 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, Elko, NV at 12:00Z on 2021-08-17Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 77 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Elko, NV at 12:00Z on 2021-08-17The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 152 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
77 J/kg
Mixed-layer CIN
-255 J/kg
Mixed-layer LCL
3040 m above ground
0-6 km bulk shear
35 kt
0-1 km storm-relative helicity
152 m²/s²
0-3 km storm-relative helicity
158 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

216 
WUUS55 KSLC 172229
SVRSLC
UTC045-172315-
/O.NEW.KSLC.SV.W.0072.210817T2229Z-210817T2315Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Salt Lake City UT
429 PM MDT Tue Aug 17 2021

The National Weather Service in Salt Lake City has issued a

* Severe Thunderstorm Warning for...
  Southwestern Tooele County in northern Utah...

* Until 515 PM MDT

* At 429 PM MDT, a severe thunderstorm was located 17 miles west of
  Dugway Proving Ground Test Range, or 42 miles west of Dugway
  English Village, moving northeast at 40 mph.

  HAZARD...60 mph wind gusts and penny size hail. 

  SOURCE...Radar indicated. 

  IMPACT...Expect damage to roofs, siding, and trees. 

* Locations impacted include...
  Dugway Proving Ground Test Range.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

Large hail and damaging winds and continuous cloud to ground
lightning is occurring with this storm. Move indoors immediately.
Lightning is one of nature's leading killers. Remember, if you can
hear thunder, you are close enough to be struck by lightning.

&&

LAT...LON 3991 11367 4019 11370 4044 11290 4020 11283
      3991 11281
TIME...MOT...LOC 2229Z 247DEG 34KT 4014 11355 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...0.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

MPS
1 follow-up statement
923 
WWUS55 KSLC 172248
SVSSLC

Severe Weather Statement
National Weather Service Salt Lake City UT
448 PM MDT Tue Aug 17 2021

UTC045-172315-
/O.CON.KSLC.SV.W.0072.000000T0000Z-210817T2315Z/
Tooele UT-
448 PM MDT Tue Aug 17 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 515 PM MDT
FOR SOUTH CENTRAL TOOELE COUNTY...

At 447 PM MDT, a severe thunderstorm was located near Dugway Proving
Ground Test Range, or 31 miles west of Dugway English Village, moving
northeast at 40 mph.

HAZARD...60 mph wind gusts and penny size hail. 

SOURCE...Radar indicated. 

IMPACT...Expect damage to roofs, siding, and trees. 

Locations impacted include...
Dugway Proving Ground Test Range.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

Continuous cloud to ground lightning is occurring with this storm.
Move indoors immediately. Lightning is one of nature's leading
killers. Remember, if you can hear thunder, you are close enough to
be struck by lightning.

&&

LAT...LON 3991 11367 4023 11358 4044 11290 4020 11283
      3991 11281
TIME...MOT...LOC 2247Z 247DEG 34KT 4021 11334 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...0.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

MPS

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 17, 1:31 PM MDTSpecial Weather StatementSLCKane44 min
Aug 17, 1:50 PM MDTSevere Thunderstorm WarningSLCGarfield, Kane20 min
Aug 17, 2:23 PM MDTSevere Thunderstorm WarningSLCBeaver, Garfield, Piute52 min
Aug 17, 2:50 PM MDTFlash Flood Warning Considerable damage threatSLCGarfield3 hr
Aug 17, 3:14 PM MDTSpecial Weather StatementSLCJuab31 min
Aug 17, 3:20 PM MDTSpecial Weather StatementSLCTooele25 min
Aug 17, 3:29 PM MDTSevere Thunderstorm WarningSLCSevier46 min
Aug 17, 3:51 PM MDTSevere Thunderstorm WarningSLCTooele24 min
Aug 17, 4:12 PM MDTSevere Thunderstorm Warning Considerable damage threatSLCTooele48 min
Aug 17, 4:18 PM MDTFlash Flood Warning Considerable damage threatSLCEmery, Wayne3 hr
Aug 17, 4:39 PM MDTSevere Thunderstorm Warning Considerable damage threatSLCMillard66 min
Aug 17, 4:53 PM MDTFlash Flood Warning Considerable damage threatSLCGarfield3 hr
Aug 17, 4:56 PM MDTSevere Thunderstorm WarningSLCGarfield24 min
Aug 17, 5:00 PM MDTSevere Thunderstorm WarningSLCDavis, Salt Lake, Tooele30 min
Aug 17, 5:10 PM MDTFlash Flood Warning Considerable damage threatSLCKane4 hr
Aug 17, 5:12 PM MDTSevere Thunderstorm WarningSLCTooele63 min
Aug 17, 5:30 PM MDTSevere Thunderstorm Warning Considerable damage threatSLCDavis, Salt Lake45 min
Aug 17, 5:37 PM MDTFlash Flood Warning Considerable damage threatSLCGarfield, Kane6 hr
Aug 17, 5:40 PM MDTSevere Thunderstorm WarningSLCMillard50 min
Aug 17, 5:48 PM MDTSpecial Weather StatementSLCSanpete27 min

Nearby

Severe Thunderstorm Warnings in Utah, 2021Every severe thunderstorm warning 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.