Alert archive / Utah / Severe Thunderstorm Warnings in 2021
Severe Thunderstorm Warning 104, NWS Salt Lake City, UT
NWS Salt Lake City, UT issued this severe thunderstorm warning at Sep 10, 2021, 6:20 PM MDT for Davis County, Morgan County, Weber County, Utah. It was in force for 25 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, 6:20 PM MDT (00:20 UTC)
- Expired
- Sep 10, 2021, 6:45 PM MDT
- In force
- 25 min
- Issued by
- NWS Salt Lake City, UT
- Area
- Storm-based polygon
- Hail
- 0.75 in
- Wind
- 60.0 mph
Counties Davis County, UT, Morgan County, UT, Weber County, UT
The radar
The Salt Lake City radar (KMTX), 43 km from the middle of the area, began a volume at 00:22 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, 0.3 hours before the alert went out and 39 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.
- 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
The text
As transmitted.
610
WUUS55 KSLC 110020
SVRSLC
UTC011-029-057-110045-
/O.NEW.KSLC.SV.W.0104.210911T0020Z-210911T0045Z/
BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Salt Lake City UT
620 PM MDT Fri Sep 10 2021
The National Weather Service in Salt Lake City has issued a
* Severe Thunderstorm Warning for...
Southwestern Weber County in northern Utah...
Northeastern Davis County in northern Utah...
West central Morgan County in northern Utah...
* Until 645 PM MDT
* At 620 PM MDT, strong outflow winds associated with thunderstorms
were located along a line extending from 6 miles west of Hooper to
9 miles southwest of Syracuse, moving northeast at 25 mph.
HAZARD...60 mph wind gusts.
SOURCE...Radar indicated.
IMPACT...Expect damage to roofs, siding, and trees.
* Locations impacted include...
Ogden, Layton, Farmington, Hill Air Force Base, Roy, Clearfield,
Kaysville, Syracuse, Clinton, North Ogden, South Ogden,
Centerville, Washington Terrace, Riverdale, Hooper, South Weber,
Marriott-Slaterville, Uintah, Weber State University and South
Willard.
This includes the following highways...
Interstate 15 between mile markers 322 and 351.
Interstate 84 between mile markers 82 and 91.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
Wind damage with these storms will occur before any rain or
lightning. Do not wait for the sound of thunder before taking cover.
SEEK SHELTER IMMEDIATELY inside a sturdy structure and stay away from
windows.
&&
LAT...LON 4122 11189 4115 11185 4102 11184 4097 11178
4089 11217 4118 11233 4136 11199
TIME...MOT...LOC 0020Z 240DEG 20KT 4116 11224 4097 11214
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH
$$
Webber2 follow-up statements
106
WWUS55 KSLC 110037
SVSSLC
Severe Weather Statement
National Weather Service Salt Lake City UT
637 PM MDT Fri Sep 10 2021
UTC011-029-057-110045-
/O.CON.KSLC.SV.W.0104.000000T0000Z-210911T0045Z/
Weber UT-Davis UT-Morgan UT-
637 PM MDT Fri Sep 10 2021
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 645 PM MDT
FOR SOUTHWESTERN WEBER...NORTHEASTERN DAVIS AND WEST CENTRAL MORGAN
COUNTIES...
At 636 PM MDT, outflow winds associated with strong thunderstorms
were located along a line extending from Ogden to 8 miles west of
West Bountiful, moving east at 40 mph.
HAZARD...60 mph wind gusts.
SOURCE...Radar indicated.
IMPACT...Expect damage to roofs, siding, and trees.
Locations impacted include...
Ogden, Layton, Farmington, Hill Air Force Base, Roy, Clearfield,
Kaysville, Syracuse, Clinton, North Ogden, South Ogden, Centerville,
Washington Terrace, Riverdale, Hooper, South Weber,
Marriott-Slaterville, Uintah, Weber State University and South
Willard.
This includes the following highways...
Interstate 15 between mile markers 322 and 351.
Interstate 84 between mile markers 82 and 91.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
Wind damage with these storms will occur before any rain or
lightning. Do not wait for the sound of thunder before taking cover.
SEEK SHELTER IMMEDIATELY inside a sturdy structure and stay away from
windows.
&&
LAT...LON 4122 11189 4115 11185 4102 11184 4097 11178
4089 11217 4118 11233 4136 11199
TIME...MOT...LOC 0036Z 283DEG 36KT 4121 11198 4091 11207
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH
$$
CRK167
WWUS55 KSLC 110044 RRA
SVSSLC
Severe Weather Statement
National Weather Service Salt Lake City UT
644 PM MDT Fri Sep 10 2021
UTC011-029-057-110054-
/O.EXP.KSLC.SV.W.0104.000000T0000Z-210911T0045Z/
Weber UT-Davis UT-Morgan UT-
644 PM MDT Fri Sep 10 2021
...THE SEVERE THUNDERSTORM WARNING FOR SOUTHWESTERN WEBER...
NORTHEASTERN DAVIS AND WEST CENTRAL MORGAN COUNTIES WILL EXPIRE AT
645 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. A special weather
statement is now in effect for this line, with gusts to 55 mph
possible.
LAT...LON 4122 11189 4115 11185 4102 11184 4097 11178
4089 11217 4118 11233 4136 11199
TIME...MOT...LOC 0044Z 240DEG 20KT 4123 11193 4093 11202
$$
CRKThe office that day
Everything else NWS Salt Lake City, UT issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 10, 6:06 PM MDT | Severe Thunderstorm Warning | SLC | Box Elder, Weber | 39 min |
| Sep 10, 6:42 PM MDT | Special Weather Statement | SLC | Morgan, Weber | 33 min |
| Sep 10, 6:42 PM MDT | Special Weather Statement | SLC | Davis | 33 min |
| Sep 10, 6:50 PM MDT | Severe Thunderstorm Warning | SLC | Davis, Salt Lake, Tooele | 25 min |
| Sep 10, 7:10 PM MDT | Special Weather Statement | SLC | Salt Lake, Utah | 50 min |
| Sep 10, 7:10 PM MDT | Severe Thunderstorm Warning | SLC | Davis, Morgan, Salt Lake, Weber | 35 min |
| Sep 10, 7:16 PM MDT | Severe Thunderstorm Warning | SLC | Davis, Salt Lake | 29 min |
| Sep 10, 7:24 PM MDT | Special Weather Statement | SLC | Rich | 51 min |
| Sep 10, 7:24 PM MDT | Special Weather Statement | SLC | Cache | 51 min |
| Sep 10, 7:38 PM MDT | Special Weather Statement | SLC | Cache, Morgan, Rich, Weber | 52 min |
| Sep 11, 12:50 PM MDT | Flash Flood Warning | SLC | Wayne | 3 hr |
| Sep 11, 12:54 PM MDT | Special Weather Statement | SLC | Carbon | 51 min |
| Sep 11, 1:39 PM MDT | Special Weather Statement | SLC | Duchesne | 51 min |
| Sep 11, 1:40 PM MDT | Flash Flood Warning | SLC | Carbon | 3 hr |
| Sep 11, 3:17 PM MDT | Special Weather Statement | SLC | Duchesne | 43 min |
| Sep 11, 4:25 PM MDT | Special Weather Statement | SLC | Millard | 35 min |
| Sep 11, 5:10 PM MDT | Special Weather Statement | SLC | Juab | 35 min |
| Sep 11, 5:19 PM MDT | Special Weather Statement | SLC | Millard | 26 min |
| Sep 11, 5:44 PM MDT | Special Weather Statement | SLC | Millard | 46 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.