Alert archive / Utah / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 45, NWS Salt Lake City, UT

July 29, 2021Beaver County, Iron County, Utah

NWS Salt Lake City, UT issued this severe thunderstorm warning at Jul 29, 2021, 2:39 PM MDT for Beaver County, Iron County, Utah. It was in force for 36 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 29, 2021, 2:39 PM MDT (20:39 UTC)
Expired
Jul 29, 2021, 3:15 PM MDT
In force
36 min
Issued by
NWS Salt Lake City, UT
Area
Storm-based polygon
Hail
1.5 in
Wind
60.0 mph

Counties Beaver County, UT, Iron County, UT

The radar

The Cedar City radar (KICX), 79 km from the middle of the area, began a volume at 20:39 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, 8.7 hours before the alert went out and 285 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, Salt Lake City I, UT at 12:00Z on 2021-07-29Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 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, Salt Lake City I, UT at 12:00Z on 2021-07-29The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 8 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1489 m above ground
0-6 km bulk shear
6 kt
0-1 km storm-relative helicity
8 m²/s²
0-3 km storm-relative helicity
-5 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

162 
WUUS55 KSLC 292039
SVRSLC
UTC001-021-292115-
/O.NEW.KSLC.SV.W.0045.210729T2039Z-210729T2115Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Salt Lake City UT
239 PM MDT Thu Jul 29 2021

The National Weather Service in Salt Lake City has issued a

* Severe Thunderstorm Warning for...
  Eastern Beaver County in southern Utah...
  Northeastern Iron County in southern Utah...

* Until 315 PM MDT

* At 239 PM MDT, a severe thunderstorm was located near Beaver,
  moving northeast at 5 mph.

  HAZARD...Ping pong ball size hail and 60 mph wind gusts. 

  SOURCE...Radar indicated. 

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

* Locations impacted include...
  Beaver and Manderfield. 

This includes the following highways...
 Interstate 15 between mile markers 105 and 121.
 Utah Route 21 between mile markers 100 and 107.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 3812 11249 3828 11284 3851 11284 3837 11250
TIME...MOT...LOC 2039Z 233DEG 5KT 3832 11270 

HAIL...1.50IN
WIND...60MPH
 
$$

ND
2 follow-up statements
508 
WWUS55 KSLC 292054
SVSSLC

Severe Weather Statement
National Weather Service Salt Lake City UT
254 PM MDT Thu Jul 29 2021

UTC021-292104-
/O.CAN.KSLC.SV.W.0045.000000T0000Z-210729T2115Z/
Iron UT-
254 PM MDT Thu Jul 29 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN IRON COUNTY IS
CANCELLED...
    
The severe thunderstorm which prompted the warning has moved out of 
the warned area. Therefore, the warning has been cancelled.

LAT...LON 3819 11252 3828 11284 3851 11284 3839 11255
TIME...MOT...LOC 2054Z 233DEG 5KT 3833 11268 

$$

UTC001-292115-
/O.CON.KSLC.SV.W.0045.000000T0000Z-210729T2115Z/
Beaver UT-
254 PM MDT Thu Jul 29 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 315 PM MDT
FOR EASTERN BEAVER COUNTY...

At 254 PM MDT, a severe thunderstorm was located near Beaver, moving
northeast at 5 mph.

HAZARD...Ping pong ball size hail and 60 mph wind gusts. 

SOURCE...Radar indicated. 

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

Locations impacted include...
Beaver and Manderfield. 

This includes the following highways...
 Interstate 15 between mile markers 108 and 121.
 Utah Route 21 between mile markers 101 and 107.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 3819 11252 3828 11284 3851 11284 3839 11255
TIME...MOT...LOC 2054Z 233DEG 5KT 3833 11268 

HAIL...1.50IN
WIND...60MPH
 
$$

ND
056 
WWUS55 KSLC 292110
SVSSLC

Severe Weather Statement
National Weather Service Salt Lake City UT
310 PM MDT Thu Jul 29 2021

UTC001-292119-
/O.EXP.KSLC.SV.W.0045.000000T0000Z-210729T2115Z/
Beaver UT-
310 PM MDT Thu Jul 29 2021

...THE SEVERE THUNDERSTORM WARNING FOR EASTERN BEAVER COUNTY WILL
EXPIRE AT 315 PM MDT...
                
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 will be allowed to expire.  However small
hail, gusty winds and heavy rain are still possible with this
thunderstorm.

LAT...LON 3819 11252 3828 11284 3851 11284 3839 11255
TIME...MOT...LOC 2109Z 233DEG 5KT 3834 11266 

$$

ND

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 28, 7:56 PM MDTSpecial Weather StatementSLCTooele49 min
Jul 28, 9:52 PM MDTSpecial Weather StatementSLCDavis83 min
Jul 29, 2:38 AM MDTFlash Flood WatchSLCEmery, Garfield, Kane, San Juan, Sevier, Washington and 1 more21 hr
Jul 29, 1:40 PM MDTSpecial Weather StatementSLCIron20 min
Jul 29, 2:00 PM MDTSevere Thunderstorm WarningSLCIron, Washington30 min
Jul 29, 2:17 PM MDTSpecial Weather StatementSLCPiute28 min
Jul 29, 2:26 PM MDTSpecial Weather StatementSLCBeaver34 min
Jul 29, 2:50 PM MDTAreal Flood AdvisorySLCBeaver115 min
Jul 29, 3:13 PM MDTSpecial Weather StatementSLCBeaver32 min
Jul 29, 3:33 PM MDTSpecial Weather StatementSLCIron27 min
Jul 29, 3:54 PM MDTSpecial Weather StatementSLCMillard36 min
Jul 29, 4:11 PM MDTSpecial Weather StatementSLC34 min
Jul 29, 4:22 PM MDTSpecial Weather StatementSLCJuab23 min
Jul 29, 4:37 PM MDTSpecial Weather StatementSLCGarfield23 min
Jul 29, 4:48 PM MDTSevere Thunderstorm WarningSLCGarfield, Iron27 min
Jul 29, 4:54 PM MDTSevere Thunderstorm WarningSLCPiute, Sevier36 min
Jul 29, 5:18 PM MDTSpecial Weather StatementSLCGarfield27 min
Jul 29, 5:42 PM MDTSevere Thunderstorm WarningSLCGarfield33 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.