Alert archive / Utah / Winter Weather Advisories in 2021
Winter Weather Advisory 25, NWS Salt Lake City, UT
NWS Salt Lake City, UT issued this winter weather advisory at Dec 25, 2021, 2:13 AM MST for 18 counties in Utah; Uinta County, Wyoming. It took effect at Dec 25, 2021, 11:00 PM MST. It was in force for 13 hr.
The area
The counties it named.
The facts
- Issued
- Dec 25, 2021, 2:13 AM MST (09:13 UTC)
- In effect from
- Dec 25, 2021, 11:00 PM MST
- Expired
- Dec 26, 2021, 12:12 PM MST
- In force
- 13 hr
- Issued by
- NWS Salt Lake City, UT
Counties Beaver County, UT, Box Elder County, UT, Cache County, UT, Carbon County, UT, Duchesne County, UT, Emery County, UT, Iron County, UT, Juab County, UT, Millard County, UT, Morgan County, UT, Rich County, UT, Sanpete County, UT, Sevier County, UT, Summit County, UT, Utah County, UT, Wasatch County, UT, Washington County, UT, Weber County, UT, Uinta County, WY
The radar
The Salt Lake City radar (KMTX), 154 km from the middle of the area, began a volume at 09:11 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
Elko, NV (KLKN), launched 00:00Z, 9.2 hours before the alert went out and 224 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
- 70 J/kg
- Mixed-layer CIN
- -17 J/kg
- Mixed-layer LCL
- 817 m above ground
- 0-6 km bulk shear
- 72 kt
- 0-1 km storm-relative helicity
- 275 m²/s²
- 0-3 km storm-relative helicity
- 407 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.1
What forecasters said that day
The local office's own words before this winter weather advisory went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Salt Lake City, UT wrote its last area forecast discussion before this winter weather advisory went out at Dec 24, 10:25 PM MST, 3 hours 48 minutes earlier.
Area forecast discussion, Dec 24, 10:25 PM MST, 3 hours 48 minutes before
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</html>The office that day
Everything else NWS Salt Lake City, UT issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Dec 25, 2:13 AM MST | Winter Storm Warning | SLC | Beaver, Box Elder, Cache, Davis, Duchesne, Garfield and 13 more | 36 hr |
| Dec 25, 2:09 PM MST | Wind Advisory | SLC | Beaver, Box Elder, Davis, Duchesne, Emery, Garfield and 13 more | 25 hr |
Nearby
Winter Weather Advisories in Utah, 2021Winter Weather Advisories in Wyoming, 2021Every winter weather advisory 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.