Strong winds developed across portions of Utah on April 12 in association with a cold front.
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.
Strong winds developed across portions of Utah on April 12 in association with a cold front.
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 Apr 11, 8:48 PM MST, 5 hours 42 minutes earlier.
Area Forecast Discussion
National Weather Service Salt Lake City UT
948 PM MDT Wed Apr 11 2018
.SYNOPSIS...A mild southwesterly flow will remain across the
region through late tonight. A substantially colder storm system
will impact the region Thursday into Friday, with high pressure
returning for the weekend.
&&
.DISCUSSION...Southwesterly flow aloft continues to increase across
the forecast area this evening ahead of an upper trough currently
moving across the West Coast states. MSAS MSLP analysis indicates a
997mb low currently over west-central Utah and east-central Nevada
which will continue to deepen overnight ahead of the trough. As it
does so, southerly winds south and southeast of this low will
continue to strengthen, and gusts over 40 mph have already been
reported in this area. Meanwhile, 700mb winds of 45-60kt tonight may
occasionally mix down in the form of stronger gusts, although for
the most part, the airmass should remain decoupled.
Weak returns on radar corresponding to light precipitation or virga
have lingered across northwest Utah along the northwestern periphery
of the surface low and associated with a 700mb thermal gradient.
This boundary will move across northern Utah after midnight as
colder air associated with the advancing trough starts to catch up
to it. The front will then quickly move across the remainder of Utah
by the early afternoon hours. Precipitation will spread into the
area behind this cold front, increasing through the morning hours.
Although valleys are expected to see rain initially, snow levels are
expected to fall rapidly, due not just to the cold air moving in,
but precipitation intensities as well. However, given the time of
day, accumulations in the valleys are not expected to be
significant. Mountains will see greater accumulations with the
frontal band, after which cooler air aloft leading to steeper lapse
rates later in the afternoon and overnight hours will drive
orographic precipitation favoring northwest-facing slopes and
adjacent upslope valleys.
Strong post-frontal winds will also be a concern, especially in
favored downslope regions, especially the northwest deserts and the
eastern valleys. These strong winds are expected to continue through
Thursday night and even into Friday morning across the eastern
valleys.
As far as highlights, will not make any changes at this time. The
existing winter weather highlights seem to be handled well. The wind
highlights are fine for now but could eventually need some
modifications. For example, given a strong westerly gradient with
the passage of the cold front tomorrow, Utah's Dixie may benefit
from a Wind Advisory, but will allow the midnight shift to make that
call. In addition, the High Wind Warning for Castle Country may need
to go longer than its current end time, as downslope wind potential
seems to only be peaking around that time. However, there is still
plenty of time to allow the situation to evolve before jumping all
in on an extension.
Otherwise, just made some minor adjustments to the forecast to
increase sky cover down south and to tweak winds and evening PoPs.
&&
.AVIATION...The SLC terminal will see VFR conditions through late
tonight with CIGS above 7kft. Northwest winds are expected to switch
to southerly by 06z, then back to northwest and becoming stronger
behind a cold front around 11z. However, there is a 30 percent
chance the southerly winds will not develop. CIGS will lower near
the cold front as precipitation begins to develop in the morning.
Rain is expected to start changing to snow during the late morning
through early afternoon timeframe, with MVFR/IFR conditions
developing. Little to no snow accumulation is expected on treated
surfaces.
&&
.SLC WATCHES/WARNINGS/ADVISORIES...
UT...Wind Advisory from 9 AM to 6 PM MDT Thursday for UTZ020-021.
Winter Weather Advisory from 6 AM Thursday to noon MDT Friday
for UTZ007-009-010.
Winter Storm Warning from 6 AM Thursday to noon MDT Friday for
UTZ008.
High Wind Warning from 6 AM Thursday to 6 AM MDT Friday for
UTZ005.
Wind Advisory from 6 AM to 9 PM MDT Thursday for UTZ004.
Winter Weather Advisory from noon Thursday to noon MDT Friday
for UTZ517-518.
High Wind Warning until noon MDT Thursday for UTZ015-016.
High Wind Warning from noon Thursday to 6 AM MDT Friday for
UTZ011-012.
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.phpHazardous Weather Outlook National Weather Service Salt Lake City UT 327 PM MDT Wed Apr 11 2018 UTZ001>016-019>021-517-518-WYZ021-121300- 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- 327 PM MDT Wed Apr 11 2018 This Hazardous Weather Outlook is for the western two thirds of Utah and southwest Wyoming. .DAY ONE...This Afternoon and Tonight South winds will strengthen through this evening across west central and southwest Utah, potentially gusting in excess of 60 mph late this evening and overnight. .DAYS TWO THROUGH SEVEN...Thursday through Tuesday A strong cold front will bring much colder temperatures to the outlook area Thursday through Friday. Significant snow accumulations are expected across the higher terrain during this time, with snow levels falling to the valley floors of western Utah including the I-15 corridor from the Idaho Border to Cedar City. Accumulations are expected on grassy and elevated surfaces, particularly along the benches of the Wasatch Front south to near Fillmore and Beaver. Strong south to southwest winds are expected to continue Thursday morning across west central and southwest Utah, then spread into south central Utah, Lake Powell, and possibly the San Rafael Swell late morning through afternoon. Behind this front strong northwest winds gusting in excess of 60 mph are possible across northwest Utah as well as the western Uinta Basin and Castle Country. A much colder airmass behind this front will drop overnight low temperatures below freezing in many valley locations both Thursday and Friday nights. High pressure is expected to bring a warming trend over the weekend, with another cold storm system expected late Monday into Tuesday. .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
6 high wind. Local standard time, as filed.
The U.S. 6 at Eureka sensor reported a peak wind gust of 71 mph, while the I-15 at the Sevier River sensor reported a peak wind gust of 64 mph.
Peak gusts of 58 mph were recorded at Vernon and Flight Park South.
Maximum record wind gusts included 72 mph in Wendover, 66 mph at Promontory Point, 64 mph in Lucin, 63 mph at Lakeside Mountain, and 58 mph at Gunnison Island.
Maximum record wind gusts included 84 mph at Arrowhead Summit and 75 mph at Great Western, Lookout Mountain, and the Central Wasatch Peaks.
Bullfrog Marina reported a peak wind gust of 63 mph.
A maximum wind gust of 80 mph was reported at Hogan Pass.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Utah in 2018Every state in 2018This day in weather historyWarnings in Utah, April 2018
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: 748330, 748328, 748336, 748339, 748342, 748341.