A deep upper level trough dominated the western United States and kicked out a series of Pacific systems across the region. This wave train impacted eastern Utah for several days and produced heavy snow in the mountains as well as very strong winds.
Every event with a place to put it; 2 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS GJT wrote it up.
A deep upper level trough dominated the western United States and kicked out a series of Pacific systems across the region. This wave train impacted eastern Utah for several days and produced heavy snow in the mountains as well as very strong winds.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Grand Junction, CO wrote its last area forecast discussion before the first event at Dec 25, 4:49 PM MST, 5 hours 11 minutes earlier.
Area Forecast Discussion
National Weather Service Grand Junction CO
449 PM MST Sat Dec 25 2021
.SHORT TERM...(Tonight through Sunday night)
Issued at 349 PM MST Sat Dec 25 2021
Looking at the temperature forecast across the CONUS for tomorrow
there could be highs pushing 90s in the Red River Valley and
possibly not hitting minus 10 in Cut Bank Montana. This can only
mean one thing in between...wind. Lots and lots of wind. Combine
some snow with this wind and you are gonna have a mess. Check out
our home page for the latest warnings and advisories of all
flavors. Looks like the Schofield Pass area was the winner with
the last high moisture storm at 5.5 inches of liquid. This
storm...though it does get a brief feed of the AR to the
South...will not have the moisture to work with. But did I mention
the wind. The good news is less moisture and colder temperatures
aloft means we can return to champagne snow and not Sierra Cement.
The bad news is this snow will be much easier to blow around.
This is the reasoning behind the Winter Storm Warnings in place
with snow amounts generally in the 5 to 10 inch range. Winds of 55
to 70 mph will be common across the higher locales of the
mountains...driven by a Southwest to Northeast oriented 180+kt jet
overhead. Snow...blowing and drifting snow and near whiteout
conditions can be expected with next event of many to come. Winds
will also make it down to the lower elevations and there is a fine
line between snow and gusty winds in the lower elevations.
Decided the upper Yampa and Eagle/Colorado Valleys will have
enough snow mixed with the wind to warrant snow advisories.
Farther West...less snow is expected which means winds will be the
main concern so went with wind highlights here. At times there
may not be much difference with wind driven snow showers. Lower
sounding profiles suggest suggests the snow should melt as it
falls in elevations at or below 5500 feet. The winter and wind
highlights are currently where the highest confidence is placed
this afternoon and things may still change or be added. Pagosa
Springs again could be on the fringe of winter highlights with
generally 1-3 inches along the 160 corridor but less wind. Stay
tuned. Much of this storm will be wrapping up late Sunday...but
another storm is right on the heels of this one to start the new
week.
.LONG TERM...(Monday through Saturday)
Issued at 349 PM MST Sat Dec 25 2021
Height sigma charts on the storm track maps keep a deep trough in
place across Western NOAM until further notice. This means the
wave train will continue to impact much of the West as the northern
stream drifts southward through mid week. With the jet diving
farther south colder air will be filtering into the CWA and below
normal temperatures will be the normal. Our northern CWA will be
especially hit hard with highs in the basins and valleys
struggling to it the 20 degree mark in the afternoons. As
mentioned the next storm arrives by Monday mid-day with another
passing through Wednesday into Thursday before we slowly dry out
for a short spell. The storm at the end of the week could be
impressive with a mixture of southern stream moisture and northern
stream cold. Gonna be a busy weather week with many details yet to
be ironed out. The skiing will be improved but the travel getting there
may not.
&&
.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
Issued at 448 PM MST Sat Dec 25 2021
Few to scattered skies this evening will give way to increasing
cloud cover overnight and increasing winds aloft, leading to
areas of LLWS. Showers will increase late tonight across the
mountains with some lower valleys seeing showers by late Sunday
morning into the afternoon. Expect deep mixing at all TAF sites
Sunday with wind gusts in the 30s and 40s common at most TAF sites
with stronger gusts at higher elevations. This will result in
areas of blowing snow and lowered visibilities in areas where it
does snow with some rain or a rain/snow mix in lower elevations.
Anticipate MVFR to be common with areas of IFR/LIFR in heavy snow
and blowing snow. ILS breakpoints expected to be reached due to
lower CIGS with the passage of this system Sunday morning through
the evening.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...Wind Advisory from 8 AM to 4 PM MST Sunday for COZ001-006-011-
020.
Winter Weather Advisory from 2 AM Sunday to 5 AM MST Monday for
COZ003-005-017-018.
Winter Storm Warning from 2 AM Sunday to 5 AM MST Monday for
COZ004-009-010-012-013-019.
Winter Weather Advisory from 2 AM to 11 PM MST Sunday for COZ002-
008.
UT...Wind Advisory from 8 AM to 4 PM MST Sunday for UTZ022-027-029.
Winter Storm Warning from 11 PM this evening to 5 AM MST Monday
for UTZ023.
Winter Weather Advisory from 2 AM Sunday to 5 AM MST Monday for
UTZ028.
&&
SHORT TERM...15
LONG TERM...15
AVIATION...MDAHazardous Weather Outlook National Weather Service Grand Junction CO 441 AM MST Sat Dec 25 2021 COZ001>014-017>023-UTZ022>025-027>029-261145- Lower Yampa River Basin-Central Yampa River Basin- Roan and Tavaputs Plateaus-Elkhead and Park Mountains- Upper Yampa River Basin-Grand Valley-Debeque to Silt Corridor- Central Colorado River Basin-Grand and Battlement Mesas- Gore and Elk Mountains/Central Mountain Valleys- Central Gunnison and Uncompahgre River Basin- West Elk and Sawatch Mountains-Flat Tops- Upper Gunnison River Valley-Uncompahgre Plateau and Dallas Divide- Northwest San Juan Mountains-Southwest San Juan Mountains- Paradox Valley/Lower Dolores River- Four Corners/Upper Dolores River-Animas River Basin- San Juan River Basin-Southeast Utah-Eastern Uinta Mountains- Eastern Uinta Basin-Tavaputs Plateau-Arches/Grand Flat- La Sal and Abajo Mountains-Canyonlands/Natural Bridges- 441 AM MST Sat Dec 25 2021 This hazardous weather outlook is for eastern Utah and western Colorado. .DAY ONE...Today and Tonight Snow will decrease in coverage and intensity throughout the day with light additional accumulations. Gusty winds to 40 mph over the high passes will result in blowing snow. Snow increases tonight as the next in a series of storms begins to impact the region. .DAYS TWO THROUGH SEVEN...Sunday through Friday Wind and snow increase on Sunday as a strong disturbance moves through the area. It's likely this system will bring very strong winds and significant snowfall accumulations across the mountains. Wind combined with snow may result in whiteout conditions for travelers in the high country. A seemingly endless series of disturbances will move across the region throughout the week ahead bringing continued snow chances for much of the region. .SPOTTER INFORMATION STATEMENT... Spotter activation is not expected today or tonight, however spotters are encouraged to report snowfall amounts to the National Weather Service in Grand Junction.
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
439 PM MST SAT DEC 25 2021
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0439 PM HEAVY SNOW 2 SSW TELLURIDE 37.91N 107.83W
12/25/2021 M8.5 INCH SAN MIGUEL CO PUBLIC
&&PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
440 PM MST SAT DEC 25 2021
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0839 AM HEAVY RAIN 7 WNW DOVE CREEK 37.81N 109.01W
12/25/2021 M0.33 INCH DOLORES CO CO-OP OBSERVER
&&PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
441 PM MST SAT DEC 25 2021
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
1041 AM HEAVY RAIN 5 NW MACK 39.27N 108.93W
12/25/2021 M0.50 INCH MESA CO TRAINED SPOTTER
&&PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
445 PM MST SAT DEC 25 2021
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0944 AM SNOW 1 SSW DURANGO 37.27N 107.88W
12/25/2021 M2.0 INCH LA PLATA CO PUBLIC
24 HOUR SNOWFALL TOTAL AND CURRENT SNOW
DEPTH ON GROUND.
&&PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
556 PM MST SAT DEC 25 2021
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0556 PM HEAVY SNOW 8 NW CIMMARON 38.53N 107.65W
12/25/2021 M6.0 INCH MONTROSE CO PUBLIC
&&PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
647 PM MST SAT DEC 25 2021
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0647 PM HEAVY SNOW HAYDEN 40.49N 107.25W
12/24/2021 M14.0 INCH ROUTT CO CO-OP OBSERVER
&&The national radar mosaic for the moment the first event began.
1 winter storm, 1 winter weather. Local standard time, as filed.
Generally 8 to 12 inches of snow fell across the area. Winds gusted up to 51 mph.
Generally 4 to 9 inches of snow fell across the area with locally higher amounts of up to 15 inches estimated at the La Sal Mountain SNOTEL site.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Utah in 2021Every state in 2021This day in weather historyWarnings in Utah, December 2021
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 990938, 990939.