Alert archive / Utah / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 15, NWS Salt Lake City, UT

July 14, 2021Washington County, Utah

NWS Salt Lake City, UT issued this severe thunderstorm warning at Jul 14, 2021, 7:53 PM MDT for Washington County, Utah. It was in force for 69 min. 4 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: Jul 14, 2021, 7:53 PM MDT (01:53 UTC)
Expired: Jul 14, 2021, 9:02 PM MDT
In force: 69 min
Issued by: NWS Salt Lake City, UT
Area: Storm-based polygon
Hail: 0.75 in
Wind: 60.0 mph

County Washington County, UT

The radar

The Cedar City radar (KICX), 71 km from the middle of the area, began a volume at 01:57 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

Time	Report	Where	Remark
Jul 14, 8:03 PM MDT	TSTM WND DMG	6 Ne Gunlock, UT	POWER LINES DOWN IN VEYO
Jul 14, 8:24 PM MDT	TSTM WND DMG	Santa Clara, UT	POWER LINES DOWN AND POWER OUT IN TOWN. TREES DOWN ON LAVA FLOW STREET.
Jul 14, 8:38 PM MDT	TSTM WND DMG	St George, UT	SKYLIGHTS BLOWN OFF ROOF. HEAVY RAIN FALLING INTO HOME.
Jul 14, 8:56 PM MDT	TSTM WND DMG	Washington, UT	POWER LINES DOWN IN WASHINGTON

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

The nearest sounding before it

Las Vegas, NV (KVEF), launched 00:00Z, 1.9 hours before the alert went out and 203 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: 523 J/kg
Mixed-layer CIN: -274 J/kg
Mixed-layer LCL: 2860 m above ground
0-6 km bulk shear: 22 kt
0-1 km storm-relative helicity: 30 m²/s²
0-3 km storm-relative helicity: 147 m²/s²
Significant tornado parameter: 0.0
Supercell composite: -0.1

Open this sounding in Storm Lab

The text

As transmitted.

040 
WUUS55 KSLC 150153
SVRSLC
UTC053-150315-
/O.NEW.KSLC.SV.W.0015.210715T0153Z-210715T0315Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Salt Lake City UT
753 PM MDT Wed Jul 14 2021

The National Weather Service in Salt Lake City has issued a

* Severe Thunderstorm Warning for...
  Washington County in southwestern Utah...

* Until 915 PM MDT

* At 753 PM MDT, severe thunderstorms were located along a line
  extending from 7 miles northwest of New Harmony to near Dameron
  Valley to 16 miles southwest of Gunlock State Park, moving
  southeast at 25 mph.

  HAZARD...60 mph wind gusts. 

  SOURCE...Radar indicated. 

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

* Locations impacted include...
  St George, Washington, Hurricane, Santa Clara, La Verkin, New
  Harmony, Dameron Valley, Quail Creek State Park, Sand Hollow State
  Park, Gunlock State Park, Ivins, Toquerville, Leeds, Virgin,
  Pintura, Bloomington, Pine Valley, Pinto, Gunlock and Veyo.

This includes the following highways...
 Interstate 15 between mile markers 1 and 37.
 Utah Route 18 between mile markers 0 and 30.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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

&&

LAT...LON 3727 11405 3737 11376 3757 11348 3753 11347
      3753 11331 3752 11329 3720 11312 3700 11333
      3701 11405
TIME...MOT...LOC 0153Z 332DEG 20KT 3752 11342 3731 11371 3715 11404 

HAIL...<.75IN
WIND...60MPH
 
$$

Church

2 follow-up statements

464 
WWUS55 KSLC 150240
SVSSLC

Severe Weather Statement
National Weather Service Salt Lake City UT
840 PM MDT Wed Jul 14 2021

UTC053-150315-
/O.CON.KSLC.SV.W.0015.000000T0000Z-210715T0315Z/
Washington UT-
840 PM MDT Wed Jul 14 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 915 PM MDT
FOR SOUTHERN WASHINGTON COUNTY...

At 840 PM MDT, severe thunderstorms were located along a line
extending from 7 miles north of La Verkin to St George to near Virgin
River Gorge, moving east at 25 mph.

HAZARD...60 mph wind gusts. 

SOURCE...Radar indicated. 

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

Locations impacted include...
St George, Washington, Hurricane, Santa Clara, La Verkin, Quail Creek
State Park, Sand Hollow State Park, Ivins, Toquerville, Leeds,
Virgin, Pintura, Bloomington and Snow Canyon State Park.

This includes the following highways...
 Interstate 15 between mile markers 1 and 35.
 Utah Route 18 between mile markers 0 and 10.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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

&&

LAT...LON 3714 11405 3723 11361 3739 11324 3720 11312
      3700 11333 3701 11405
TIME...MOT...LOC 0240Z 270DEG 20KT 3731 11326 3710 11355 3694 11388 

HAIL...<.75IN
WIND...60MPH
 
$$

Church

200 
WWUS55 KSLC 150302
SVSSLC

Severe Weather Statement
National Weather Service Salt Lake City UT
902 PM MDT Wed Jul 14 2021

UTC053-150309-
/O.CAN.KSLC.SV.W.0015.000000T0000Z-210715T0315Z/
Washington UT-
902 PM MDT Wed Jul 14 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHERN WASHINGTON COUNTY IS
CANCELLED...
    
The storms which prompted the warning have moved out of the area.
Therefore, the warning has been cancelled.

To report severe weather, contact your nearest law enforcement
agency. They will relay your report to the National Weather Service
Salt Lake City.

LAT...LON 3714 11405 3723 11361 3739 11324 3720 11312
      3700 11333 3701 11405
TIME...MOT...LOC 0259Z 332DEG 20KT 3722 11320 3700 11349 3684 11382 

$$

Church

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 14, 6:20 PM MDT	Special Weather Statement	SLC	Emery	40 min
Jul 14, 6:25 PM MDT	Severe Thunderstorm Warning	SLC	Iron, Washington	50 min
Jul 14, 6:49 PM MDT	Special Weather Statement	SLC	Iron	41 min
Jul 14, 7:07 PM MDT	Flash Flood Warning Considerable damage threat	SLC	Kane, Washington	3 hr
Jul 15, 2:53 AM MDT	Flash Flood Watch	SLC	Beaver, Emery, Garfield, Iron, Kane, Piute and 4 more	25 hr
Jul 15, 4:43 PM MDT	Special Weather Statement	SLC	Carbon	47 min
Jul 15, 5:01 PM MDT	Special Weather Statement	SLC	Garfield	44 min
Jul 15, 5:03 PM MDT	Special Weather Statement	SLC	Tooele	57 min
Jul 15, 5:29 PM MDT	Special Weather Statement	SLC	Weber	61 min

Nearby

Severe Thunderstorm Warnings in Utah, 2021 Every 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.