Alert archive / Utah / Severe Thunderstorm Warnings in 2021
Severe Thunderstorm Warning 87, NWS Salt Lake City, UT
NWS Salt Lake City, UT issued this severe thunderstorm warning at Aug 21, 2021, 5:42 PM MDT for Davis County, Salt Lake County, Tooele County, Utah. It was in force for 33 min. 7 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
- Aug 21, 2021, 5:42 PM MDT (23:42 UTC)
- Expired
- Aug 21, 2021, 6:15 PM MDT
- In force
- 33 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, Tooele County, UT
The radar
The Salt Lake City radar (KMTX), 73 km from the middle of the area, began a volume at 23:42 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 |
|---|---|---|---|
| Aug 21, 5:45 PM MDT | TSTM WND GST 58 | 1 Se Delle, UT | MEASURED AT UDOT I-80 AT MP 71 EAST DELLE SENSOR. |
| Aug 21, 6:00 PM MDT | TSTM WND DMG | Kaysville, UT | TREE DOWN AND DAMAGED PORTION OF FENCE |
| Aug 21, 6:00 PM MDT | NON-TSTM WND DMG | Kaysville, UT | TREE DOWN AND DAMAGED PORTION OF FENCE |
| Aug 21, 6:19 PM MDT | TSTM WND GST 65 | Woods Cross, UT | TREE BRANCHES DOWN. |
| Aug 21, 6:20 PM MDT | TSTM WND GST 59 | 4 Nw Magna, UT | |
| Aug 21, 6:20 PM MDT | TSTM WND GST 73 | 4 Nne Stansbury Park, UT | |
| Aug 21, 6:21 PM MDT | TSTM WND GST 63 | 1 Wsw Farmington, UT | MEASURED AT A PERSONAL WEATHER STATION IN FARMINGTON |
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, 11.7 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
- 77 J/kg
- Mixed-layer CIN
- -271 J/kg
- Mixed-layer LCL
- 2167 m above ground
- 0-6 km bulk shear
- 35 kt
- 0-1 km storm-relative helicity
- 239 m²/s²
- 0-3 km storm-relative helicity
- 260 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.1
The text
As transmitted.
701
WUUS55 KSLC 212342
SVRSLC
UTC011-035-045-220015-
/O.NEW.KSLC.SV.W.0087.210821T2342Z-210822T0015Z/
BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Salt Lake City UT
542 PM MDT Sat Aug 21 2021
The National Weather Service in Salt Lake City has issued a
* Severe Thunderstorm Warning for...
Western Salt Lake County in northern Utah...
Davis County in northern Utah...
Northeastern Tooele County in northern Utah...
* Until 615 PM MDT
* At 542 PM MDT, severe thunderstorms were located along a line
extending from 15 miles northwest of Great Salt Lake South of the
Causeway to 15 miles west of Skull Valley, moving east 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, Layton, Bountiful, Tooele,
Farmington, Grantsville, West Jordan, South Jordan, Kaysville,
North Salt Lake, Centerville, Woods Cross, Stansbury Park, West
Bountiful, Ophir, Kearns, Delle, Salt Lake City International
Airport and Tooele Army Depot.
This includes the following highways...
Interstate 15 between mile markers 314 and 315, and between mile
markers 317 and 330.
Interstate 80 in Utah between mile markers 66 and 117.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
&&
LAT...LON 4103 11270 4106 11257 4106 11184 4101 11183
4044 11211 4047 11213 4046 11222 4034 11217
4033 11220 4029 11219 4010 11228 4035 11310
TIME...MOT...LOC 2342Z 285DEG 38KT 4115 11262 4042 11304
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...OBSERVED
MAX WIND GUST...60 MPH
$$
CRK1 follow-up statement
140
WWUS55 KSLC 212352
SVSSLC
Severe Weather Statement
National Weather Service Salt Lake City UT
552 PM MDT Sat Aug 21 2021
UTC011-035-045-220015-
/O.CON.KSLC.SV.W.0087.000000T0000Z-210822T0015Z/
Salt Lake UT-Davis UT-Tooele UT-
552 PM MDT Sat Aug 21 2021
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 615 PM MDT
FOR WESTERN SALT LAKE...DAVIS AND NORTHEASTERN TOOELE COUNTIES...
At 550 PM MDT, severe thunderstorms were located along a line
extending from 11 miles northwest of Great Salt Lake South of the
Causeway to 11 miles west of Skull Valley, moving east at 45 mph.
HAZARD...60 mph wind gusts.
SOURCE...Trained weather spotters.
IMPACT...Expect damage to roofs, siding, and trees.
Locations impacted include...
Salt Lake City, West Valley City, Layton, Bountiful, Tooele,
Farmington, Grantsville, West Jordan, South Jordan, Kaysville, North
Salt Lake, Centerville, Woods Cross, Stansbury Park, West Bountiful,
Ophir, Kearns, Delle, Salt Lake City International Airport and Tooele
Army Depot.
This includes the following highways...
Interstate 15 between mile markers 314 and 315, and between mile
markers 317 and 330.
Interstate 80 in Utah between mile markers 66 and 117.
This lines of storms has a history of producing wind gusts to 65 mph
even behind the main area of thunderstorms.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
&&
LAT...LON 4103 11270 4106 11257 4106 11184 4101 11183
4044 11211 4047 11213 4046 11222 4034 11217
4033 11220 4029 11219 4010 11228 4035 11310
TIME...MOT...LOC 2350Z 285DEG 38KT 4113 11254 4040 11296
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...OBSERVED
MAX WIND GUST...60 MPH
$$
CRKThe office that day
Everything else NWS Salt Lake City, UT issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 21, 1:25 PM MDT | Special Weather Statement | SLC | Rich | 50 min |
| Aug 21, 3:14 PM MDT | Special Weather Statement | SLC | Box Elder | 61 min |
| Aug 21, 4:31 PM MDT | Special Weather Statement | SLC | Tooele | 59 min |
| Aug 21, 4:34 PM MDT | Special Weather Statement | SLC | Cache | 56 min |
| Aug 21, 5:10 PM MDT | Special Weather Statement | SLC | Davis | 20 min |
| Aug 21, 5:19 PM MDT | Special Weather Statement | SLC | Davis | 26 min |
| Aug 21, 5:27 PM MDT | Severe Thunderstorm Warning | SLC | Box Elder, Cache, Davis, Morgan, Weber | 48 min |
| Aug 21, 5:52 PM MDT | Severe Thunderstorm Warning | SLC | Box Elder, Cache | 38 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.