Alert archive / Utah / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 16, NWS Salt Lake City, UT

July 15, 2021Iron County, Utah

NWS Salt Lake City, UT issued this severe thunderstorm warning at Jul 15, 2021, 7:08 PM MDT for Iron County, Utah. It was in force for 52 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
Jul 15, 2021, 7:08 PM MDT (01:08 UTC)
Expired
Jul 15, 2021, 8:00 PM MDT
In force
52 min
Issued by
NWS Salt Lake City, UT
Area
Storm-based polygon
Hail
1.75 in
Wind
50.0 mph

County Iron County, UT

The radar

The Cedar City radar (KICX), 75 km from the middle of the area, began a volume at 01:11 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

Las Vegas, NV (KVEF), launched 00:00Z, 1.1 hours before the alert went out and 260 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, Las Vegas, NV at 00:00Z on 2021-07-16Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 688 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, Las Vegas, NV at 00:00Z on 2021-07-16The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 9 square meters per square second.1939Sfc1 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
688 J/kg
Mixed-layer CIN
-18 J/kg
Mixed-layer LCL
3158 m above ground
0-6 km bulk shear
12 kt
0-1 km storm-relative helicity
9 m²/s²
0-3 km storm-relative helicity
16 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

849 
WUUS55 KSLC 160108
SVRSLC
UTC021-160200-
/O.NEW.KSLC.SV.W.0016.210716T0108Z-210716T0200Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Salt Lake City UT
708 PM MDT Thu Jul 15 2021

The National Weather Service in Salt Lake City has issued a

* Severe Thunderstorm Warning for...
  North central Iron County in southern Utah...

* Until 800 PM MDT

* At 708 PM MDT, a severe thunderstorm was located 33 miles southwest
  of Milford, and is nearly stationary.

  HAZARD...Golf ball size hail. 

  SOURCE...Radar indicated. 

  IMPACT...People and animals outdoors will be injured. Expect 
           damage to roofs, siding, windows, and vehicles. 

* Locations impacted include...
  Lund.

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 3800 11360 3815 11358 3815 11331 3796 11335
TIME...MOT...LOC 0108Z 266DEG 1KT 3809 11349 

HAIL...1.75IN
WIND...<50MPH
 
$$

Church
2 follow-up statements
756 
WWUS55 KSLC 160130
SVSSLC

Severe Weather Statement
National Weather Service Salt Lake City UT
730 PM MDT Thu Jul 15 2021

UTC021-160200-
/O.CON.KSLC.SV.W.0016.000000T0000Z-210716T0200Z/
Iron UT-
730 PM MDT Thu Jul 15 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 800 PM MDT
FOR NORTH CENTRAL IRON COUNTY...

At 730 PM MDT, a severe thunderstorm was located 32 miles southwest
of Milford, and is nearly stationary.

HAZARD...Golf ball size hail. 

SOURCE...Radar indicated. 

IMPACT...People and animals outdoors will be injured. Expect damage 
         to roofs, siding, windows, and vehicles. 

Locations impacted include...
Lund.

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 3800 11360 3815 11358 3815 11331 3796 11335
TIME...MOT...LOC 0130Z 266DEG 1KT 3809 11348 

HAIL...1.75IN
WIND...<50MPH
 
$$

Church
030 
WWUS55 KSLC 160201
SVSSLC

Severe Weather Statement
National Weather Service Salt Lake City UT
801 PM MDT Thu Jul 15 2021

UTC021-160210-
/O.EXP.KSLC.SV.W.0016.000000T0000Z-210716T0200Z/
Iron UT-
801 PM MDT Thu Jul 15 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTH CENTRAL IRON COUNTY HAS
EXPIRED...
                
The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore, the warning has been allowed to expire.  However small
hail and heavy rain are still possible with this thunderstorm.

LAT...LON 3800 11360 3815 11358 3815 11331 3796 11335
TIME...MOT...LOC 0200Z 266DEG 1KT 3809 11347 

$$

Church

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 15, 6:35 PM MDTSpecial Weather StatementSLCSalt Lake40 min
Jul 15, 8:39 PM MDTFlash Flood Warning Considerable damage threatSLCBeaver, Iron3 hr
Jul 16, 12:39 AM MDTFlash Flood Warning Considerable damage threatSLCKane, Washington3 hr
Jul 16, 1:05 AM MDTFlash Flood Warning Considerable damage threatSLCKane, Washington3 hr
Jul 16, 1:09 AM MDTAreal Flood AdvisorySLCWashington3 hr
Jul 16, 1:07 PM MDTSpecial Weather StatementSLCKane38 min
Jul 16, 1:27 PM MDTFlash Flood Warning Considerable damage threatSLCKane3 hr
Jul 16, 1:58 PM MDTFlash Flood Warning Considerable damage threatSLCGarfield, Kane3 hr
Jul 16, 3:20 PM MDTSpecial Weather StatementSLC40 min
Jul 16, 3:47 PM MDTFlash Flood Warning Considerable damage threatSLCGarfield, Kane3 hr
Jul 16, 4:46 PM MDTSpecial Weather StatementSLCMillard44 min
Jul 16, 5:04 PM MDTSevere Thunderstorm WarningSLCMillard56 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.