Alert archive / Utah / Severe Thunderstorm Warnings in 2021
Severe Thunderstorm Warning 94, NWS Salt Lake City, UT
NWS Salt Lake City, UT issued this severe thunderstorm warning at Aug 21, 2021, 8:19 PM MDT for Duchesne County, Summit County, Utah. It was in force for 26 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
- Aug 21, 2021, 8:19 PM MDT (02:19 UTC)
- Expired
- Aug 21, 2021, 8:45 PM MDT
- In force
- 26 min
- Issued by
- NWS Salt Lake City, UT
- Area
- Storm-based polygon
- Hail
- 1.0 in
- Wind
- 60.0 mph
Counties Duchesne County, UT, Summit County, UT
The radar
The Salt Lake City radar (KMTX), 206 km from the middle of the area, began a volume at 02:21 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, 2.3 hours before the alert went out and 153 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
- 422 J/kg
- Mixed-layer CIN
- -7 J/kg
- Mixed-layer LCL
- 2862 m above ground
- 0-6 km bulk shear
- 50 kt
- 0-1 km storm-relative helicity
- 84 m²/s²
- 0-3 km storm-relative helicity
- 171 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 2.1
The text
As transmitted.
664
WUUS55 KSLC 220219
SVRSLC
UTC013-043-220245-
/O.NEW.KSLC.SV.W.0094.210822T0219Z-210822T0245Z/
BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Salt Lake City UT
819 PM MDT Sat Aug 21 2021
The National Weather Service in Salt Lake City has issued a
* Severe Thunderstorm Warning for...
Northeastern Duchesne County in northern Utah...
East central Summit County in northern Utah...
* Until 845 PM MDT
* At 819 PM MDT, a severe thunderstorm was located 21 miles northwest
of Whiterocks, moving northeast at 35 mph.
HAZARD...60 mph wind gusts and quarter size hail.
SOURCE...Radar indicated.
IMPACT...Hail damage to vehicles is expected. Expect wind damage
to roofs, siding, and trees.
* This severe thunderstorm will remain over mainly rural areas of
northeastern Duchesne and east central Summit Counties.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
&&
LAT...LON 4064 11016 4076 11029 4097 11000 4082 11000
4080 10998 4071 10998
TIME...MOT...LOC 0219Z 232DEG 31KT 4074 11015
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH
$$
Webber1 follow-up statement
556
WWUS55 KSLC 220235
SVSSLC
Severe Weather Statement
National Weather Service Salt Lake City UT
835 PM MDT Sat Aug 21 2021
UTC013-043-220245-
/O.EXP.KSLC.SV.W.0094.000000T0000Z-210822T0245Z/
Duchesne UT-Summit UT-
835 PM MDT Sat Aug 21 2021
...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN DUCHESNE AND EAST
CENTRAL SUMMIT COUNTIES WILL EXPIRE AT 845 PM MDT...
The storm which prompted the warning has weakened below severe
limits, and has exited the warned area. Therefore, the warning will
be allowed to expire.
LAT...LON 4064 11016 4076 11029 4097 11000 4082 11000
4080 10998 4071 10998
TIME...MOT...LOC 0235Z 232DEG 31KT 4082 11002
$$
WebberThe office that day
Everything else NWS Salt Lake City, UT issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 21, 6:06 PM MDT | Severe Thunderstorm Warning | SLC | Box Elder, Cache, Davis, Morgan, Rich, Salt Lake and 3 more | 39 min |
| Aug 21, 6:29 PM MDT | Severe Thunderstorm Warning | SLC | Cache, Rich | 61 min |
| Aug 21, 6:40 PM MDT | Severe Thunderstorm Warning | SLC | Box Elder, Cache, Davis, Morgan, Rich, Salt Lake and 3 more | 50 min |
| Aug 21, 6:59 PM MDT | Areal Flood Advisory | SLC | Davis, Weber | 2 hr |
| Aug 21, 7:08 PM MDT | Severe Thunderstorm Warning | SLC | Summit | 37 min |
| Aug 21, 7:23 PM MDT | Special Weather Statement | SLC | Salt Lake | 37 min |
| Aug 21, 7:33 PM MDT | Areal Flood Advisory | SLC | Davis, Morgan, Salt Lake, Summit | 117 min |
| Aug 21, 7:41 PM MDT | Special Weather Statement | SLC | Summit | 49 min |
| Aug 21, 7:49 PM MDT | Special Weather Statement | SLC | Duchesne | 41 min |
| Aug 21, 8:09 PM MDT | Special Weather Statement | SLC | Summit | 51 min |
| Aug 21, 8:14 PM MDT | Special Weather Statement | SLC | 31 min | |
| Aug 21, 8:32 PM MDT | High Wind Warning | SLC | Utah | 3 hr |
| Aug 21, 9:59 PM MDT | Flash Flood Warning | SLC | Salt Lake | 91 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.