Alert archive / Utah / Severe Thunderstorm Warnings in 2021
Severe Thunderstorm Warning 110, NWS Salt Lake City, UT
NWS Salt Lake City, UT issued this severe thunderstorm warning at Sep 12, 2021, 4:31 PM MDT for Box Elder County, Utah. It was in force for 44 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 12, 2021, 4:31 PM MDT (22:31 UTC)
- Expired
- Sep 12, 2021, 5:15 PM MDT
- In force
- 44 min
- Issued by
- NWS Salt Lake City, UT
- Area
- Storm-based polygon
- Hail
- 1.0 in
- Wind
- 60.0 mph
County Box Elder County, UT
The radar
The Salt Lake City radar (KMTX), 74 km from the middle of the area, began a volume at 22:34 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 12:00Z, 10.5 hours before the alert went out and 144 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
- 108 J/kg
- Mixed-layer CIN
- -195 J/kg
- Mixed-layer LCL
- 1716 m above ground
- 0-6 km bulk shear
- 32 kt
- 0-1 km storm-relative helicity
- 76 m²/s²
- 0-3 km storm-relative helicity
- 124 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
593
WUUS55 KSLC 122231
SVRSLC
UTC003-122315-
/O.NEW.KSLC.SV.W.0110.210912T2231Z-210912T2315Z/
BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Salt Lake City UT
431 PM MDT Sun Sep 12 2021
The National Weather Service in Salt Lake City has issued a
* Severe Thunderstorm Warning for...
North central Box Elder County in northern Utah...
* Until 515 PM MDT
* At 430 PM MDT, a severe thunderstorm was located near Juniper, or
19 miles west of Snowville, moving east at 25 mph. An additional
severe thunderstorm is located northeast of Park Valley, moving
east at 25 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...
Snowville, Park Valley and Curlew Junction.
This includes the following highways...
Interstate 84 between mile markers 0 and 16.
Utah Route 30 between mile markers 55 and 90.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
&&
LAT...LON 4174 11256 4182 11336 4200 11318 4200 11256
TIME...MOT...LOC 2230Z 270DEG 23KT 4196 11309
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH
$$
CRK1 follow-up statement
272 WWUS55 KSLC 122255 SVSSLC Severe Weather Statement National Weather Service Salt Lake City UT 455 PM MDT Sun Sep 12 2021 UTC003-122315- /O.CON.KSLC.SV.W.0110.000000T0000Z-210912T2315Z/ Box Elder UT- 455 PM MDT Sun Sep 12 2021 ...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 515 PM MDT FOR NORTH CENTRAL BOX ELDER COUNTY... At 455 PM MDT, a severe thunderstorm was located near Juniper, or 9 miles west of Snowville, moving east at 20 mph. HAZARD...60 mph wind gusts and penny size hail. SOURCE...Radar indicated. IMPACT...Expect damage to roofs, siding, and trees. Locations impacted include... Snowville and Curlew Junction. This includes the following highways... Interstate 84 between mile markers 0 and 16. Utah Route 30 between mile markers 68 and 90. PRECAUTIONARY/PREPAREDNESS ACTIONS... For your protection move to an interior room on the lowest floor of a building. && LAT...LON 4181 11256 4187 11314 4200 11305 4200 11256 TIME...MOT...LOC 2255Z 271DEG 19KT 4199 11290 HAIL THREAT...RADAR INDICATED MAX HAIL SIZE...0.75 IN WIND THREAT...RADAR INDICATED MAX WIND GUST...60 MPH $$ CRK
The office that day
Everything else NWS Salt Lake City, UT issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 11, 6:19 PM MDT | Flash Flood Warning | SLC | Emery, Garfield, Wayne | 3 hr |
| Sep 11, 6:30 PM MDT | Special Weather Statement | SLC | Juab | 45 min |
| Sep 11, 7:16 PM MDT | Special Weather Statement | SLC | Juab | 44 min |
| Sep 11, 7:24 PM MDT | Special Weather Statement | SLC | 51 min | |
| Sep 11, 8:15 PM MDT | Flash Flood Warning | SLC | Garfield, Wayne | 3 hr |
| Sep 11, 8:22 PM MDT | Special Weather Statement | SLC | Sanpete | 38 min |
| Sep 11, 9:06 PM MDT | Special Weather Statement | SLC | Sanpete | 39 min |
| Sep 12, 3:29 PM MDT | Special Weather Statement | SLC | Box Elder | 46 min |
| Sep 12, 3:37 PM MDT | Severe Thunderstorm Warning | SLC | Box Elder | 23 min |
| Sep 12, 3:54 PM MDT | Severe Thunderstorm Warning | SLC | Box Elder | 51 min |
| Sep 12, 4:13 PM MDT | Special Weather Statement | SLC | Box Elder | 47 min |
| Sep 12, 4:42 PM MDT | Severe Thunderstorm Warning | SLC | Box Elder | 24 min |
| Sep 12, 5:08 PM MDT | Severe Thunderstorm Warning | SLC | Box Elder | 20 min |
| Sep 12, 5:14 PM MDT | Special Weather Statement | SLC | 46 min | |
| Sep 12, 5:54 PM MDT | Severe Thunderstorm Warning | SLC | Box Elder | 51 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.