Alert archive / Utah / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 107, NWS Salt Lake City, UT

September 10, 2021Davis County, Salt Lake County, Utah

NWS Salt Lake City, UT issued this severe thunderstorm warning at Sep 10, 2021, 7:16 PM MDT for Davis County, Salt Lake County, Utah. It was in force for 29 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
Sep 10, 2021, 7:16 PM MDT (01:16 UTC)
Expired
Sep 10, 2021, 7:45 PM MDT
In force
29 min
Issued by
NWS Salt Lake City, UT
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

Counties Davis County, UT, Salt Lake County, UT

The radar

The Salt Lake City radar (KMTX), 88 km from the middle of the area, began a volume at 01:16 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 00:00Z, 1.3 hours before the alert went out and 22 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 00:00Z on 2021-09-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 430 joules per kilogram.LCLEL10008507005003002001001 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 00:00Z on 2021-09-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 128 square meters per square second.193958Sfc1 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
430 J/kg
Mixed-layer CIN
-39 J/kg
Mixed-layer LCL
3241 m above ground
0-6 km bulk shear
38 kt
0-1 km storm-relative helicity
128 m²/s²
0-3 km storm-relative helicity
161 m²/s²
Significant tornado parameter
0.0
Supercell composite
2.2

Open this sounding in Storm Lab

The text

As transmitted.

876 
WUUS55 KSLC 110116
SVRSLC
UTC011-035-110145-
/O.NEW.KSLC.SV.W.0107.210911T0116Z-210911T0145Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Salt Lake City UT
716 PM MDT Fri Sep 10 2021

The National Weather Service in Salt Lake City has issued a

* Severe Thunderstorm Warning for...
  Central Salt Lake County in northern Utah...
  Southeastern Davis County in northern Utah...

* Until 745 PM MDT

* At 716 PM MDT, severe thunderstorms were located along a line
  extending from West Valley City to Bluffdale, moving northeast at
  45 mph.

  HAZARD...60 mph wind gusts. 

  SOURCE...Radar indicated. 

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

* Locations impacted include...
  Salt Lake City, West Valley City, Sandy, Murray, Bountiful, West
  Jordan, Taylorsville, South Jordan, Draper, Riverton, Cottonwood
  Heights, Midvale, Holladay, South Salt Lake, Herriman, North Salt
  Lake, Woods Cross, Bluffdale, Millcreek and Kearns.

This includes the following highways...
 Interstate 15 between mile markers 286 and 315.
 Interstate 80 in Utah between mile markers 113 and 130.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4093 11180 4053 11172 4052 11178 4049 11179
      4047 11186 4048 11188 4043 11192 4042 11199
      4046 11204 4045 11207 4073 11212 4076 11205
TIME...MOT...LOC 0116Z 211DEG 48KT 4071 11201 4048 11199 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

CRK
2 follow-up statements
517 
WWUS55 KSLC 110131
SVSSLC

Severe Weather Statement
National Weather Service Salt Lake City UT
731 PM MDT Fri Sep 10 2021

UTC011-035-110145-
/O.CON.KSLC.SV.W.0107.000000T0000Z-210911T0145Z/
Salt Lake UT-Davis UT-
731 PM MDT Fri Sep 10 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 745 PM MDT
FOR CENTRAL SALT LAKE AND SOUTHEASTERN DAVIS COUNTIES...

At 731 PM MDT, severe thunderstorms were located along a line
extending from Bountiful to near Draper, moving northeast at 35 mph.

HAZARD...60 mph wind gusts. 

SOURCE...Radar indicated. 

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

Locations impacted include...
Salt Lake City, West Valley City, Sandy, Murray, Bountiful,
Taylorsville, Draper, Cottonwood Heights, Midvale, Holladay, South
Salt Lake, North Salt Lake, Millcreek, Granite, Cottonwood West,
Mount Olympus, Little Cottonwood Creek Valley, East Millcreek, Canyon
Rim and Emigration Canyon.

This includes the following highways...
 Interstate 15 between mile markers 295 and 313.
 Interstate 80 in Utah between mile markers 118 and 130.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4093 11180 4053 11172 4052 11178 4049 11179
      4047 11186 4048 11188 4081 11195
TIME...MOT...LOC 0131Z 211DEG 31KT 4087 11188 4050 11181 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

CRK
584 
WWUS55 KSLC 110142
SVSSLC

Severe Weather Statement
National Weather Service Salt Lake City UT
742 PM MDT Fri Sep 10 2021

UTC011-035-110152-
/O.EXP.KSLC.SV.W.0107.000000T0000Z-210911T0145Z/
Salt Lake UT-Davis UT-
742 PM MDT Fri Sep 10 2021

...THE SEVERE THUNDERSTORM WARNING FOR CENTRAL SALT LAKE AND
SOUTHEASTERN DAVIS COUNTIES WILL EXPIRE AT 745 PM MDT...
            
The storms which prompted the warning have weakened below severe
limits, and no longer pose an immediate threat to life or property.
Therefore, the warning will be allowed to expire.  However gusty
winds are still possible with these thunderstorms.

LAT...LON 4093 11180 4053 11172 4052 11178 4049 11179
      4047 11186 4048 11188 4081 11195
TIME...MOT...LOC 0142Z 211DEG 48KT 4092 11183 4055 11176 

$$

CRK

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 10, 6:06 PM MDTSevere Thunderstorm WarningSLCBox Elder, Weber39 min
Sep 10, 6:20 PM MDTSevere Thunderstorm WarningSLCDavis, Morgan, Weber25 min
Sep 10, 6:42 PM MDTSpecial Weather StatementSLCMorgan, Weber33 min
Sep 10, 6:42 PM MDTSpecial Weather StatementSLCDavis33 min
Sep 10, 6:50 PM MDTSevere Thunderstorm WarningSLCDavis, Salt Lake, Tooele25 min
Sep 10, 7:10 PM MDTSpecial Weather StatementSLCSalt Lake, Utah50 min
Sep 10, 7:10 PM MDTSevere Thunderstorm WarningSLCDavis, Morgan, Salt Lake, Weber35 min
Sep 10, 7:24 PM MDTSpecial Weather StatementSLCRich51 min
Sep 10, 7:24 PM MDTSpecial Weather StatementSLCCache51 min
Sep 10, 7:38 PM MDTSpecial Weather StatementSLCCache, Morgan, Rich, Weber52 min
Sep 11, 12:50 PM MDTFlash Flood Warning Considerable damage threatSLCWayne3 hr
Sep 11, 12:54 PM MDTSpecial Weather StatementSLCCarbon51 min
Sep 11, 1:39 PM MDTSpecial Weather StatementSLCDuchesne51 min
Sep 11, 1:40 PM MDTFlash Flood Warning Considerable damage threatSLCCarbon3 hr
Sep 11, 3:17 PM MDTSpecial Weather StatementSLCDuchesne43 min
Sep 11, 4:25 PM MDTSpecial Weather StatementSLCMillard35 min
Sep 11, 5:10 PM MDTSpecial Weather StatementSLCJuab35 min
Sep 11, 5:19 PM MDTSpecial Weather StatementSLCMillard26 min
Sep 11, 5:44 PM MDTSpecial Weather StatementSLCMillard46 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.