Alert archive / Utah / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 4, NWS Salt Lake City, UT

May 16, 2021Box Elder County, Weber County, Utah

NWS Salt Lake City, UT issued this severe thunderstorm warning at May 16, 2021, 2:29 PM MDT for Box Elder County, Weber County, Utah. It was in force for 31 min. 1 report 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: May 16, 2021, 2:29 PM MDT (20:29 UTC)
Expired: May 16, 2021, 3:00 PM MDT
In force: 31 min
Issued by: NWS Salt Lake City, UT
Area: Storm-based polygon
Hail: 1.25 in
Wind: 60.0 mph

Counties Box Elder County, UT, Weber County, UT

The radar

The Salt Lake City radar (KMTX), 46 km from the middle of the area, began a volume at 20:32 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
May 16, 2:53 PM MDT	HAIL 0.88	North Ogden, UT

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

The nearest sounding before it

Salt Lake City I, UT (KSLC), launched 12:00Z, 8.5 hours before the alert went out and 58 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: 528 J/kg
Mixed-layer CIN: -208 J/kg
Mixed-layer LCL: 1618 m above ground
0-6 km bulk shear: 28 kt
0-1 km storm-relative helicity: 22 m²/s²
0-3 km storm-relative helicity: 51 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.5

Open this sounding in Storm Lab

The text

As transmitted.

034 
WUUS55 KSLC 162029
SVRSLC
UTC003-057-162100-
/O.NEW.KSLC.SV.W.0004.210516T2029Z-210516T2100Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Salt Lake City UT
229 PM MDT Sun May 16 2021

The National Weather Service in Salt Lake City has issued a

* Severe Thunderstorm Warning for...
  Central Weber County in northern Utah...
  Eastern Box Elder County in northern Utah...

* Until 300 PM MDT

* At 229 PM MDT, a severe thunderstorm was located 7 miles east of
  Ogden, moving northwest at 25 mph.

  HAZARD...60 mph wind gusts and half dollar size hail. 

  SOURCE...Radar indicated. 

  IMPACT...Hail damage to vehicles is expected. Expect wind damage 
           to roofs, siding, and trees. 

* Locations impacted include...
  Ogden, Brigham City, North Ogden, Perry, Willard,
  Marriott-Slaterville, South Willard, Pleasant View, Farr West,
  Harrisville, Plain City, Huntsville, Eden, Liberty, Warren,
  Snowbasin and Slaterville.

This includes Interstate 15 between mile markers 345 and 362.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4126 11170 4119 11187 4131 11222 4151 11203
TIME...MOT...LOC 2029Z 122DEG 21KT 4126 11183 

HAIL...1.25IN
WIND...60MPH
 
$$

Webber

1 follow-up statement

601 
WWUS55 KSLC 162046
SVSSLC

Severe Weather Statement
National Weather Service Salt Lake City UT
246 PM MDT Sun May 16 2021

UTC003-057-162100-
/O.CON.KSLC.SV.W.0004.000000T0000Z-210516T2100Z/
Weber UT-Box Elder UT-
246 PM MDT Sun May 16 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 300 PM MDT
FOR NORTH CENTRAL WEBER AND EASTERN BOX ELDER COUNTIES...

At 246 PM MDT, a severe thunderstorm was located over North Ogden, or
near Ogden, moving northwest at 25 mph.

HAZARD...60 mph wind gusts and half dollar size hail. 

SOURCE...Radar indicated. 

IMPACT...Hail damage to vehicles is expected. Expect wind damage to 
         roofs, siding, and trees. 

Locations impacted include...
Ogden, Brigham City, North Ogden, Perry, Willard,
Marriott-Slaterville, South Willard, West Haven, Pleasant View, Farr
West, Harrisville, Plain City, Eden, Liberty, Warren and Slaterville.

This includes Interstate 15 between mile markers 345 and 362.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4132 11178 4121 11194 4131 11222 4151 11203
TIME...MOT...LOC 2046Z 122DEG 21KT 4131 11195 

HAIL...1.25IN
WIND...60MPH
 
$$

Webber

The office that day

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

Issued	Product	Office	Counties	Lasted
May 15, 6:30 PM MDT	Special Weather Statement	SLC		45 min
May 16, 1:07 PM MDT	Special Weather Statement	SLC	Salt Lake	38 min
May 16, 1:22 PM MDT	Severe Thunderstorm Warning	SLC	Davis, Salt Lake, Tooele	23 min
May 16, 1:52 PM MDT	Special Weather Statement	SLC	Davis	38 min
May 16, 1:55 PM MDT	Special Weather Statement	SLC	Salt Lake	35 min
May 16, 1:58 PM MDT	Special Weather Statement	SLC	Weber	47 min
May 16, 2:03 PM MDT	Severe Thunderstorm Warning	SLC	Morgan, Weber	27 min
May 16, 2:07 PM MDT	Special Weather Statement	SLC		38 min
May 16, 2:20 PM MDT	Special Weather Statement	SLC	Salt Lake	40 min
May 16, 2:31 PM MDT	Special Weather Statement	SLC	Davis	44 min
May 16, 2:50 PM MDT	Special Weather Statement	SLC		55 min
May 16, 3:00 PM MDT	Severe Thunderstorm Warning	SLC	Box Elder, Weber	30 min
May 16, 3:04 PM MDT	Special Weather Statement	SLC	Tooele	41 min
May 16, 3:24 PM MDT	Severe Thunderstorm Warning	SLC	Tooele	51 min
May 16, 3:30 PM MDT	Special Weather Statement	SLC	Cache	45 min
May 16, 3:32 PM MDT	Special Weather Statement	SLC	Weber	43 min
May 16, 4:15 PM MDT	Special Weather Statement	SLC	Box Elder	45 min
May 16, 4:19 PM MDT	Special Weather Statement	SLC	Box Elder	41 min
May 16, 4:39 PM MDT	Special Weather Statement	SLC	Box Elder	51 min
May 16, 5:07 PM MDT	Special Weather Statement	SLC	Box Elder	53 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.