A strong upper level storm system and an associated vigorous cold front moved through Utah on December 15 and 16. The storm produced strong synoptic scale winds both ahead of and behind the cold front, severe thunderstorms along the front, and heavy snowfall in the mountains.
Every event with a place to put it. 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 SLC wrote it up.
A strong upper level storm system and an associated vigorous cold front moved through Utah on December 15 and 16. The storm produced strong synoptic scale winds both ahead of and behind the cold front, severe thunderstorms along the front, and heavy snowfall in the mountains.
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 Salt Lake City, UT wrote its last area forecast discussion before the first event at Dec 15, 10:20 AM MST, 5 hours 40 minutes earlier.
Area Forecast Discussion
National Weather Service Salt Lake City UT
1020 AM MST Thu Dec 15 2016
.SYNOPSIS...A windy and wet Pacific storm and associated cold
front will cross the region tonight into Saturday. Thereafter an
unseasonably cold airmass will remain entrenched across the region
into early next week.
&&
.DISCUSSION...Classic example of high Sierra shadowing occurring
upstream in satellite currently, this as the well formed
atmospheric River impinges on that region. Downstream the Great
Basin only gets the leftovers, noted by lee side subsidence and
mountain wave formation only yielding prolific high cloud cover
locally. This will change tonight into tomorrow morning as the
arctic trough currently off the OR coast continues ESE down the
Cali coast, forcing the low currently off the central Cali coast
east, shifting the river SE and opening the door for inland
penetration into the area with a net orientation from the SW
(south of the Sierra crest).
In the meantime, its a short term waiting game. Precip potential
will be increasing across the UT/ID border through the day,
associated with a tight W-E H7 thermal gradient stalled there, and
remnant from yesterday's warm front that pushed through northern
UT. Did opt to pull back on this morning's PoPs south of that
region, but of more significance increased cloud cover across the
area in this latest update.
Focus in the short term will be addressing the High Wind Watch in
effect for the southeast by noon. Will also be looking into any
need for highlights regarding snow impacts during the cold
frontal passage tomorrow afternoon, namely areas such as the
Wasatch Back and SW Wyoming. Awaiting full suite of 12z guidance
for this. Previous discussion below...
PREVIOUS DISCUSSION...A rare deep, wet, windy and complex storm
system will develop during the next 24 hours to our west. The
remnant closed low with a tropical tap is about to consolidate
with an arctic system off the Pacific coast. In addition the
southern Pacific system will boost both the wind and heavy rain
threat as it crosses Southern Utah tomorrow.
The Winter Storm Warning looks on target, mainly above 8kft. Snow
levels crash to the valley floor tomorrow afternoon and evening
which will pose impacts down at least into the benches as well.
Warnings may need to be extended across the north if Lake Effect
gets going. Valley advisories may be needed particularly southeast
of the Great Salt Lake and in the upslope region between Cedar
City and Fillmore due to precipitation intensities.
Lake Effect setup continues to look very promising tomorrow night
into Saturday southeast of the Great Salt Lake. Results from local
study (using 700T difference with +4C GSL and model low level RH)
peaks between 60-100% confidence 12Z Saturday. Its been a very
long time since Ive seen such confidence levels from this study.
Adjusting the NAM KSLC BUFKIT model, yields 500-700j/kg CAPE with
equilibrium levels near 10-12kft. Whats impressive about this
sounding, is while equilibrium levels are a bit lower than Id like
to see, the CAPE in that level is remarkable, which should support
strong updrafts over the lake, which in turn supports strong
surface convergence due to conservation of mass. Will continue to
track this potential next several shifts. Have raised PoPs and QPF
in these areas as guidance remains steady.
A second threat from this storm are synoptic winds developing
across West Central and Southwest Utah later tonight and
continuing through tomorrow evening across the remainder of
southern Utah. Have issued High Wind Warnings for the former, and
High Wind Watches for the later, as the threat starts later. These
winds are supported by 50-65kts of flow at 700mb, a 10-13mb
pressure gradient across Utah, and 6-8mb pressure falls. Post
frontal winds are not expected to be as strong, but wondering if
guidance is under-doing winds based on 6-12mb pressure rises
Friday afternoon north and northwest of SLC.
Another threat is for heavy rainfall and the potential of flash
flooding across southern Utah beginning later tonight and
continuing on through tomorrow. Concerning elements include strong
PW/Wind/IVT anomalies associated with the aforementioned storm.
The southern Pacific system is particularly interesting due to
its very rich moisture and added vertical motion. BUFKIT soundings
show a 5kft thick warm cloud layer, deep for this time of year.
Strong southerly flow will aid in even more intense rainfall on
the southern slopes. Have included heavy rainfall wording in the
forecast and a Flash Flood Watch has been issued.
&&
.AVIATION...The SLC terminal will see VFR conditions throughout the
day, with cigs remaining above 6000 feet AGL through the afternoon.
Cigs are expected to lower after about sunset with rain increasing
in the vicinity of the terminal. Southerly winds, gusty at times,
are expected to continue throughout the day but there is a 30
percent chance of brief northwesterly winds.
&&
.SLC WATCHES/WARNINGS/ADVISORIES...
UT...High Wind Watch from Friday afternoon through Friday evening for
UTZ013-019>021.
Flash Flood Watch from late tonight through Friday evening for
UTZ019-020-518.
Winter Storm Warning from 4 PM this afternoon to 4 AM MST
Saturday for UTZ007>010-517-518.
High Wind Warning from 10 PM this evening to 4 PM MST Friday for
UTZ015-016.
WY...None.
&&
DISCUSSION...Merrill/Traphagan
Previous Discussion...Rogowski
For more information from NOAA's National Weather Service visit...
http://weather.gov/saltlakecity
For frequently asked questions about the Area Forecast Discussion
visit...
http://weather.gov/saltlakecity/general/afd_faqs.phpHAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE SALT LAKE CITY UT 402 AM MST THU DEC 15 2016 UTZ001>016-019>021-517-518-WYZ021-161300- CACHE VALLEY/UTAH PORTION-NORTHERN WASATCH FRONT- SALT LAKE AND TOOELE VALLEYS-SOUTHERN WASATCH FRONT- GREAT SALT LAKE DESERT AND MOUNTAINS-WASATCH MOUNTAIN VALLEYS- WASATCH MOUNTAINS I-80 NORTH-WASATCH MOUNTAINS SOUTH OF I-80- WESTERN UINTA MOUNTAINS-WASATCH PLATEAU/BOOK CLIFFS- WESTERN UINTA BASIN-CASTLE COUNTRY-SAN RAFAEL SWELL- SANPETE/SEVIER VALLEYS-WEST CENTRAL UTAH-SOUTHWEST UTAH- UTAHS DIXIE AND ZION NATIONAL PARK-SOUTH CENTRAL UTAH- GLEN CANYON RECREATION AREA/LAKE POWELL-CENTRAL MOUNTAINS- SOUTHERN MOUNTAINS-SOUTHWEST WYOMING- 402 AM MST THU DEC 15 2016 THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE WESTERN TWO THIRDS OF UTAH AND SOUTHWEST WYOMING. .DAY ONE...TODAY AND TONIGHT FOG WILL BE LOCALLY DENSE NORTH OF SALT LAKE CITY THIS MORNING. A RARE STORM SYSTEM WILL AFFECT THE REGION BEGINNING TONIGHT...LASTING INTO SATURDAY. HEAVY SNOW IS EXPECTED ABOVE 8000 FEET. SNOW LEVELS CRASH TO THE VALLEY FLOOR WITH THE PASSAGE OF THE COLD FRONT TOMORROW AFTERNOON AND EVENING. ROAD IMPACTS WILL BE POSSIBLE SOUTHEAST OF THE GREAT SALT LAKE AND FROM CEDAR CITY TO FILLMORE DURING THIS TIME PERIOD. STRONG WINDS ARE EXPECTED AHEAD OF THE COLD FRONT ACROSS SOUTHERN UTAH AND IN THE MOUNTAINS TONIGHT THROUGH TOMORROW EVENING. GUSTY NORTHWEST WINDS WILL AFFECT PORTIONS OF THE WEST DESERT...SOUTHWEST WYOMING...UINTA BASIN AND CASTLE COUNTRY TOMORROW AFTERNOON INTO SATURDAY MORNING. THERE IS A FLASH FLOOD RISK TONIGHT AND TOMORROW ACROSS SOUTHERN UTAH. THUNDERSTORMS ACROSS THE REGION TOMORROW MAY ALSO CAUSE AREAS OF WIND DAMAGE IN ADDITION TO LOCALLY HEAVY PRECIPITATION. .DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY OTHER THAN THE WEATHER IMPACTS OUTLINED EARLIER...THERE ARE NO ADDITIONAL WEATHER THREATS ACROSS THE REGION UNTIL MID WEEK. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES. ROGOWSKI/STRUTHWOLF FOR MORE INFORMATION FROM NOAA/S NATIONAL WEATHER SERVICE VISIT... HTTP://WEATHER.GOV/SALTLAKECITY FOR INFORMATION ON POTENTIAL ROAD TRAVEL IMPACTS VISIT... HTTP://WWW.UDOTTRAFFIC.UTAH.GOV/ROADWEATHERFORECAST.ASPX
The Salt Lake City radar (KMTX), 106 km away, was scanning. The volume nearest the first event began at 16:57 UTC.
13 thunderstorm wind, 6 winter storm, 3 high wind. Local standard time, as filed.
Powder Mountain received a storm total of 18 inches of snow. In addition, winds were very strong on December 16, with peak recorded gusts of 96 mph at the Snowbasin-Straw Top sensor and 88 mph at Ogden Peak.
Storm total snowfall included 38 inches at Brighton Resort and 25 inches at Alta Ski Area. Peak wind gusts included 76 mph at the Arrowhead Summit sensor and 75 mph at Mount Baldy.
The Mt. Baldy SNOTEL in central Utah recorded 2.50 inches of liquid equivalent precipitation, or approximately 23 inches of snow.
The Kolob SNOTEL received 2.80 inches of liquid equivalent precipitation, or approximately 25 inches of snow.
The Trial Lake SNOTEL received 2.50 inches of liquid equivalent precipitation, or approximately 24 inches of snow. The peak wind gust in the area was 65 mph at Chepeta RAWS.
The Huntington Horse SNOTEL received 2.90 inches of liquid equivalent precipitation, or approximately 27 inches of snow.
The US-6 at Eureka sensor recorded a maximum wind gust of 74 mph, while a 58 mph wind gust was reported in Fillmore.
A 61 mph wind gust was recorded at the Interstate 80 at Milepost 29 sensor.
The Gunnison Island sensor reported a wind gust of 61 mph.
The West of Wildcat sensor in the U.S. Army Dugway Proving Ground mesonet recorded a peak wind gust of 63 mph.
A 59 mph wind gust was recorded at Hat Island.
A 69 mph wind gust was recorded at the Causeway sensor in the Dugway Proving Ground mesonet.
The Fremont Island sensor recorded a maximum wind gust of 73 mph.
The Great Salt Lake Marina sensor reported a wind gust of 66 mph.
A 61 mph wind gust was recorded at the Target S sensor in the U.S. Army Dugway Proving Ground mesonet.
A 61 mph wind gust was reported at the White Sage sensor in the U.S. Army Dugway Proving Ground mesonet.
The English Village sensor in the U.S. Army Dugway Proving Ground mesonet recorded a maximum wind gust of 64 mph.
A 67 mph wind gust was recorded by the SLC Airport Wind 3 sensor at Salt Lake City International Airport.
Maximum recorded wind gusts included 62 at the I-15 at Black Ridge sensor, 61 mph at the Milford Municipal Airport/Ben and Judy Briscoe Field ASOS, and 58 mph at the Cedar City Regional Airport ASOS.
The US-189 at Deer Creek sensor reported a 59 mph wind gust.
A 69 mph wind gust was recorded at the Pleasant Grove RAWS.
Peak recorded wind gusts in the Sevier Valley included 61 mph at the I-15 at Sevier River sensor, 59 mph at the I-70 at Salina sensor, and 59 mph at the Sevier Reservoir sensor.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Utah in 2016Every state in 2016This day in weather historyWarnings in Utah, December 2016
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: 670501, 670503, 670507, 670510, 670504, 670505, 670544, 670488, 670489, 670490, 670491, 670492, 670493, 670494, 670495, 670496, 670497, 670498, 670545, 670499, 670500, 670543.