Gusty canyon winds developed in far southwest Utah behind a cold front, with the strongest winds during the early morning hours of December 14.
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.
Gusty canyon winds developed in far southwest Utah behind a cold front, with the strongest winds during the early morning hours of December 14.
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 13, 9:52 PM MST, 3 hours 8 minutes earlier.
Area Forecast Discussion National Weather Service Salt Lake City UT 952 PM MST Wed Dec 13 2017 .SYNOPSIS...The strong and persistent upper ridge will retreat off the west coast over the next couple of days, allowing weather disturbances to begin eroding the strong valley inversions, with the strongest of these storms expected on Saturday. && .DISCUSSION...A shortwave trough continues to dive south through Utah this evening. Although the inversion remains firmly in place, it has weakened a bit courtesy of the the cooler airmass that came with the trough, per the 00Z KSLC sounding. In addition, with a tightening of the northwesterly gradient helping to bring increased winds to stir the airmass a bit, there is less saturation just off the surface as well. As a result, fog has not made much of an appearance this evening. If fog does redevelop tonight, it would be well after midnight or closer to tomorrow morning if/when the higher stratus dissipates. Otherwise, northern Utah valleys will more likely see visibilities mostly in the 2-5 mile range under stratus clouds. Light snow has also accompanied the trough. However, this snow has started tapering off north of I-80, which is north of the trough axis. Lingering light snow will be possible for a few more hours across the central and southern Wasatch range, Wasatch Plateau, Uintas, and adjacent valleys. Finally, northerly winds will continue to increase into southern Utah through the night. A strengthening surface gradient coupled with 50kt winds at 700mb (although cold advection is relatively modest), should yield gusty winds across Washington County tonight, strongest near canyons. High pressure builds back into the area tomorrow with inversions strengthening again. However, this is not expected to be long-lived as the next trough on Saturday is still progged to bring much colder air (around -12C at 700mb over much of northern Utah) which will likely be enough to lift the lid on the inversions. Updated the forecast mainly to tweak PoP/Sky and reduce fog coverage for the rest of the night. && .AVIATION...Redevelopment of low stratus and the potential of dense fog will continue to be the primary operational weather concern at KSLC this TAF period. Prevailing MVFR conditions are expected through late tonight in haze/fog, with stratus in the 010- 020 range redeveloping. It is anticipated that the potential for dense fog formation will hold off until after 08-10z, then a 50% chance exists for LIFR/VLIFR fog into tomorrow morning. Light snow fall out remains a potential at times overnight into tomorrow morning, with any fall out creating light accumulations on untreated surfaces. Northwesterly winds will weaken through the night. && .SLC WATCHES/WARNINGS/ADVISORIES... UT...High Wind Warning until 9 AM MST Thursday for UTZ019. WY...None. && Cheng 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.php
Hazardous Weather Outlook National Weather Service Salt Lake City UT 634 PM MST Wed Dec 13 2017 UTZ001>016-019>021-517-518-WYZ021-141315- 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- 634 PM MST Wed Dec 13 2017 This Hazardous Weather Outlook is for the western two thirds of Utah and southwest Wyoming. .DAY ONE...Tonight Patchy fog will remain in place across the northern and central Wasatch Front, the Cache and Bear Lake valleys, and over portions of the northwest desert including the I-80 corridor. The fog may become locally dense at times late tonight. Strong and gusty northerly canyon winds will develop across Washington County overnight. These winds may impact travel along the I-15 corridor through that area. .DAYS TWO THROUGH SEVEN...Thursday through Tuesday Inversion conditions will continue through at least Friday. Expect areas of fog to persist across many of the lower northern valleys through the end of the week. Urban haze and poor air quality will also continue through Friday due to the strong and persistent valley inversions across northern Utah. The next real chance to scour out the fog and haze will come Friday night through Saturday. A weather disturbance approaching from the northwest will likely bring enough wind and colder air aloft to significantly break down the inversions and push fog and haze out of the area. In addition, accumulating snow is expected across the mountains of northern Utah with this system, with perhaps an inch or two in the valleys as well. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. 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
1 high wind. Local standard time, as filed.
The Badger Spring RAWS recorded a peak wind gust of 72 mph, while the I-15 at MP 29 Tripod sensor recorded a peak wind gust of 58 mph.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Utah in 2017Every state in 2017This day in weather historyWarnings in Utah, December 2017
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: 731097.