Alert archive / Utah / Mesoscale Discussions in 2021
Mesoscale Discussion 2058
The Storm Prediction Center issued this mesoscale discussion at Dec 26, 2021, 8:06 AM MST for 8 counties in Utah; Uinta County, Wyoming. It was in force for 2 hr.
The area
The outline as issued.
The facts
- Issued
- Dec 26, 2021, 8:06 AM MST (15:06 UTC)
- Expired
- Dec 26, 2021, 10:30 AM MST
- In force
- 2 hr
- Issued by
- the Storm Prediction Center
- Concerning
- Snow squall
Counties Duchesne County, UT, Morgan County, UT, Rich County, UT, Salt Lake County, UT, Sanpete County, UT, Summit County, UT, Utah County, UT, Wasatch County, UT, Uinta County, WY
The radar
The Salt Lake City radar (KMTX), 119 km from the middle of the area, began a volume at 15:09 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, 3.1 hours before the alert went out and 58 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
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 1198 m above ground
- 0-6 km bulk shear
- 63 kt
- 0-1 km storm-relative helicity
- 356 m²/s²
- 0-3 km storm-relative helicity
- 385 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.3
The text
As transmitted.
621
ACUS11 KWNS 261507
SWOMCD
SPC MCD 261506
WYZ000-UTZ000-261730-
Mesoscale Discussion 2058
NWS Storm Prediction Center Norman OK
0906 AM CST Sun Dec 26 2021
Areas affected...southwest WY and portions of central into northeast
UT
Concerning...Snow Squall
Valid 261506Z - 261730Z
SUMMARY...Gusty winds and heavy snow will quickly reduce visibility
along an eastward-advancing cold front through late morning.
DISCUSSION...A strong cold front will continue to shift eastward
this morning into parts of southwest WY and central/northeast UT. A
snow squall associated with the front is likely to persist as the
front develops eastward. Regional radar data has shown an narrow,
but intense band of snow along the front, while surface observations
near Salt Lake City have measured gusts to around 30-40 kt and
visibility rapidly decreasing to around 1/4 mile in heavy snow with
the passage of the squall.
In addition to the squall and brief heavy snow, lightning is also
being observed within the heavy snow band. The 12z SLC RAOB as well
as morning forecast sounding data indicates 100-300 J/kg MUCAPE with
steep midlevel lapse rates present across the region. This will aid
in maintenance of the squall with periods of thunder the next few
hours across the MCD area.-
..Leitman.. 12/26/2021
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...RIW...GJT...SLC...
LAT...LON 41581164 41851129 41961105 41971060 41871012 41470976
40840978 40081017 39591075 39311156 39311208 39471244
39851252 40331217 40961175 41581164SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Dec 26, 11:00 AM MST | Mesoscale Discussion | SPC | Grand, Uintah | 3 hr |
Nearby
Mesoscale Discussions in Utah, 2021Mesoscale Discussions in Wyoming, 2021Every mesoscale discussion 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.