Alert archive / Utah / Severe Thunderstorm Warnings in 2017

Severe Thunderstorm Warning 3, NWS Salt Lake City, UT

May 6, 2017Box Elder County, Cache County, Utah

NWS Salt Lake City, UT issued this severe thunderstorm warning at May 6, 2017, 3:28 PM MDT for Box Elder County, Cache County, Utah. It was in force for 47 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
May 6, 2017, 3:28 PM MDT (21:28 UTC)
Expired
May 6, 2017, 4:15 PM MDT
In force
47 min
Issued by
NWS Salt Lake City, UT
Area
Storm-based polygon

Counties Box Elder County, UT, Cache County, UT

The radar

The Salt Lake City radar (KMTX), 51 km from the middle of the area, began a volume at 21:30 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
May 6, 3:50 PM MDTTSTM WND GST 592 Sse Tremonton, UTI-15 AT TREMONTON, UT28.
May 6, 3:50 PM MDTNON-TSTM WND GST 59Elwood, UTI-15 AT TREMONTON - 4295 FT
May 6, 4:10 PM MDTTSTM WND GST 641 Wnw Plymouth, UTI-15 AT PLYMOUTH SENSOR, UT29.
May 6, 4:10 PM MDTNON-TSTM WND GST 64Plymouth, UTI-15 AT PLYMOUTH - 4495 FT

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, 9.5 hours before the alert went out and 106 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 2017-05-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 2017-05-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 118 square meters per square second.19395878Sfc1 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
3713 m above ground
0-6 km bulk shear
34 kt
0-1 km storm-relative helicity
118 m²/s²
0-3 km storm-relative helicity
141 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

305 
WUUS55 KSLC 062128
SVRSLC
UTC003-005-062215-
/O.NEW.KSLC.SV.W.0003.170506T2128Z-170506T2215Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Salt Lake City UT
328 PM MDT SAT MAY 6 2017

The National Weather Service in Salt Lake City has issued a

* Severe Thunderstorm Warning for...
  Northwestern Cache County in Utah...
  Northeastern Box Elder County in Utah...

* Until 415 PM MDT

* At 325 PM MDT, Doppler radar indicated a severe thunderstorm
  capable of producing damaging winds in excess of 60 mph. This storm
  was located 7 miles west of Bear River City, or 8 miles southwest
  of Tremonton, and moving north at 40 mph.

* Locations impacted include...
  Brigham City, Tremonton, Cache, Bear River City, Corinne,
  Clarkston, Plymouth, Howell, Riverside, Peter, Garland, Honeyville,
  Elwood, Fielding, Deweyville, Portage, Washakie, Collinston,
  Promontory and Penrose.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Severe thunderstorms produce damaging winds, destructive hail, deadly
lightning and very heavy rain. For your protection, move to an
interior room on the lowest floor of your home or business. Heavy
rains flood roads quickly so do not drive into areas where water
covers the road.

If you are in the path of this storm, prepare immediately for 
damaging winds. People outside should move to a shelter, preferably 
inside a strong building and away from windows.

This storm has a history of producing wind damage. This is a VERY
DANGEROUS SITUATION. SEEK SHELTER NOW inside a sturdy structure and
stay away from windows!

&&

LAT...LON 4151 11202 4147 11257 4200 11267 4200 11200
TIME...MOT...LOC 2125Z 179DEG 34KT 4161 11226 

$$

GM
2 follow-up statements
518 
WWUS55 KSLC 062157
SVSSLC

Severe Weather Statement
National Weather Service Salt Lake City UT
357 PM MDT SAT MAY 6 2017

UTC003-005-062215-
/O.CON.KSLC.SV.W.0003.000000T0000Z-170506T2215Z/
Cache UT-Box Elder UT-
357 PM MDT SAT MAY 6 2017

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 415 PM MDT
FOR NORTHWESTERN CACHE AND NORTHEASTERN BOX ELDER COUNTIES...

At 355 PM MDT, Doppler radar indicated a severe thunderstorm capable
of producing damaging winds in excess of 60 mph. This storm was
located near Plymouth, or 16 miles northwest of Tremonton, moving
north at 40 mph.

Locations impacted include...
Tremonton, Cache, Clarkston, Plymouth, Howell, Riverside, Peter,
Garland, Fielding, Portage, Washakie, Collinston and Bothwell.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Severe thunderstorms produce damaging winds, destructive hail, deadly
lightning and very heavy rain. For your protection move to an
interior room on the lowest floor of your home or business. Heavy
rains flood roads quickly so do not drive into areas where water
covers the road.

This storm has a history of producing wind damage. SEEK SHELTER NOW 
inside a sturdy structure and stay away from windows!

&&

LAT...LON 4172 11201 4172 11261 4200 11267 4200 11200
TIME...MOT...LOC 2155Z 179DEG 34KT 4190 11227 

$$

GM
413 
WWUS55 KSLC 062209
SVSSLC

Severe Weather Statement
National Weather Service Salt Lake City UT
409 PM MDT SAT MAY 6 2017

UTC003-005-062218-
/O.EXP.KSLC.SV.W.0003.000000T0000Z-170506T2215Z/
Cache UT-Box Elder UT-
409 PM MDT SAT MAY 6 2017

...THE SEVERE THUNDERSTORM WARNING FOR NORTHWESTERN CACHE AND
NORTHEASTERN BOX ELDER COUNTIES WILL EXPIRE AT 415 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 gusty winds
in the 40 to 50 mph range are still possible with this thunderstorm.

LAT...LON 4172 11201 4172 11261 4200 11267 4200 11200
TIME...MOT...LOC 2208Z 179DEG 34KT 4200 11227 

$$

GM

The office that day

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

IssuedProductOfficeCountiesLasted
May 6, 10:42 AM MDTAreal Flood WarningSLCWeber7 days
May 6, 12:52 PM MDTSpecial Weather StatementSLCUtah38 min
May 6, 1:55 PM MDTSpecial Weather StatementSLCBox Elder50 min
May 6, 1:58 PM MDTSpecial Weather StatementSLCSalt Lake47 min
May 6, 2:32 PM MDTSpecial Weather StatementSLCWayne58 min
May 6, 2:41 PM MDTSevere Thunderstorm WarningSLCBox Elder, Davis, Weber49 min
May 6, 3:14 PM MDTHigh Wind WarningSLC5 hr
May 6, 3:54 PM MDTSevere Thunderstorm WarningSLCEmery, Wayne25 min

Nearby

Severe Thunderstorm Warnings in Utah, 2017Every severe thunderstorm warning in 2017

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.