Alert archive / Utah / Severe Thunderstorm Warnings in 2021
Severe Thunderstorm Warning 90, NWS Salt Lake City, UT
NWS Salt Lake City, UT issued this severe thunderstorm warning at Aug 21, 2021, 6:29 PM MDT for Cache County, Rich County, Utah. It was in force for 61 min. 1 report 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, 6:29 PM MDT (00:29 UTC)
- Expired
- Aug 21, 2021, 7:30 PM MDT
- In force
- 61 min
- Issued by
- NWS Salt Lake City, UT
- Area
- Storm-based polygon
- Hail
- 0.75 in
- Wind
- 60.0 mph
Counties Cache County, UT, Rich County, UT
The radar
The Salt Lake City radar (KMTX), 106 km from the middle of the area, began a volume at 00:29 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, 6:57 PM MDT | TSTM WND GST 59 | 5 Sse Laketown, UT | MEASURED AT THE OTTER CREEK RAWS SITE. TIME ESTIMATED BY RADAR. |
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 00:00Z, 0.5 hours before the alert went out and 122 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.
361 WUUS55 KSLC 220029 SVRSLC UTC005-033-220130- /O.NEW.KSLC.SV.W.0090.210822T0029Z-210822T0130Z/ BULLETIN - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Warning National Weather Service Salt Lake City UT 629 PM MDT Sat Aug 21 2021 The National Weather Service in Salt Lake City has issued a * Severe Thunderstorm Warning for... Northeastern Cache County in northern Utah... Northern Rich County in northern Utah... * Until 730 PM MDT * At 629 PM MDT, severe thunderstorms were located along a line extending from near Franklin to 12 miles east of Hyrum, moving northeast at 50 mph. HAZARD...60 mph wind gusts. SOURCE...Radar indicated. IMPACT...Expect damage to roofs, siding, and trees. * Locations impacted include... Logan, Laketown, Smithfield, Lewiston, Garden City, Trenton, Garden, Utah State University, Bear Lake, Benson, North Logan, Providence, Hyde Park, Richmond, Millville, River Heights, Amalga, Cornish, Beaver Mountain and Meadowville. This includes the following highways... US Route 89 between mile markers 459 and 502. Utah Route 30 between mile markers 110 and 135. PRECAUTIONARY/PREPAREDNESS ACTIONS... For your protection move to an interior room on the lowest floor of a building. && LAT...LON 4171 11105 4162 11175 4200 11210 4200 11105 TIME...MOT...LOC 0029Z 227DEG 45KT 4197 11178 4164 11161 HAIL THREAT...RADAR INDICATED MAX HAIL SIZE...<.75 IN WIND THREAT...RADAR INDICATED MAX WIND GUST...60 MPH $$ Webber
3 follow-up statements
451
WWUS55 KSLC 220043
SVSSLC
Severe Weather Statement
National Weather Service Salt Lake City UT
643 PM MDT Sat Aug 21 2021
UTC005-033-220130-
/O.CON.KSLC.SV.W.0090.000000T0000Z-210822T0130Z/
Cache UT-Rich UT-
643 PM MDT Sat Aug 21 2021
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 730 PM MDT
FOR NORTHEASTERN CACHE AND NORTHERN RICH COUNTIES...
At 640 PM MDT, severe thunderstorms were located along a line
extending from 7 miles east of Franklin to 11 miles southwest of
Laketown, moving east at 50 mph.
HAZARD...60 mph wind gusts and quarter size hail. The greatest
threat for hail exists in eastern Cache County and northern
Rich County.
SOURCE...Radar indicated.
IMPACT...Hail damage to vehicles is expected. Expect wind damage to
roofs, siding, and trees.
Locations impacted include...
Logan, Laketown, Smithfield, Lewiston, Garden City, Trenton, Garden,
Utah State University, Bear Lake, Benson, North Logan, Providence,
Hyde Park, Richmond, Millville, River Heights, Amalga, Cornish,
Beaver Mountain and Meadowville.
This includes the following highways...
US Route 89 between mile markers 459 and 502.
Utah Route 30 between mile markers 110 and 135.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
&&
LAT...LON 4171 11105 4162 11175 4200 11210 4200 11105
TIME...MOT...LOC 0040Z 270DEG 45KT 4205 11166 4172 11149
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH
$$
Webber198
WWUS55 KSLC 220048
SVSSLC
Severe Weather Statement
National Weather Service Salt Lake City UT
648 PM MDT Sat Aug 21 2021
UTC005-033-220130-
/O.CON.KSLC.SV.W.0090.000000T0000Z-210822T0130Z/
Cache UT-Rich UT-
648 PM MDT Sat Aug 21 2021
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 730 PM MDT
FOR NORTHEASTERN CACHE AND NORTHERN RICH COUNTIES...
At 647 PM MDT, a severe thunderstorm was located near Laketown,
moving northeast at 45 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.
Locations impacted include...
Laketown, Garden City, Garden, Bear Lake, Meadowville, Pickelville,
Beaver Mountain and Lakota.
This includes the following highways...
US Route 89 between mile markers 478 and 502.
Utah Route 30 between mile markers 110 and 135.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
&&
LAT...LON 4165 11149 4200 11167 4200 11105 4171 11105
TIME...MOT...LOC 0047Z 245DEG 40KT 4179 11141
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH
$$
Webber710
WWUS55 KSLC 220121
SVSSLC
Severe Weather Statement
National Weather Service Salt Lake City UT
721 PM MDT Sat Aug 21 2021
UTC005-033-220130-
/O.EXP.KSLC.SV.W.0090.000000T0000Z-210822T0130Z/
Cache UT-Rich UT-
721 PM MDT Sat Aug 21 2021
...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN CACHE AND
NORTHERN RICH COUNTIES WILL EXPIRE AT 730 PM MDT...
The storm which prompted the warning has weakened below severe
limits, and has exited the warned area. Therefore, the warning will
be allowed to expire.
LAT...LON 4165 11149 4200 11167 4200 11105 4171 11105
TIME...MOT...LOC 0120Z 227DEG 45KT 4205 11104
$$
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, 6:40 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, 8:19 PM MDT | Severe Thunderstorm Warning | SLC | Duchesne, Summit | 26 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.