Isolated thunderstorms formed over Utah on August 13, producing large hail and gusty winds.
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.
Isolated thunderstorms formed over Utah on August 13, producing large hail and gusty 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 Salt Lake City, UT wrote its last area forecast discussion before the first event at Aug 13, 8:28 AM MST, 3 hours 32 minutes earlier.
Area Forecast Discussion
National Weather Service Salt Lake City UT
928 AM MDT Sun Aug 13 2017
.SYNOPSIS...A drier airmass will start working into the area from
the west today. A cold front will move into northern Utah Monday
then stall across central Utah on Tuesday.
&&
.DISCUSSION...The weak upper level short wave that brought
convection to the nrn CWA overnight is shifting east this morning
with a few residual cells mostly east of the line between about
Logan and Green River.
Drying behind this wave is spreading into the forecast area and PW
imagery shows values falling this morning. The exception is along
the AZ border where values around an inch remain in place and
should persist today.
Expecting isolated terrain based convection from the Uintas
southward this aftn into early evening while the central Wasatch
stays quiet. There could be some development off the Raft River
range however.
The drying trend continues across the south and east Mon while the
north moistens up as the cold front moves into the CWA. This front
is forecast to be fairly strong with convection developing along
it late Mon lasting thru the night.
Expect gusty southwest winds to develop ahead of the front with
equally strong or slightly stronger north winds behind it.
Much cooler air follows the front with H7 temps falling to around
+5C over SLC by 15z Tue. This should translate into highs in the
upper 70s to low 80s Tue along the Wasatch Front.
The front stalls over central UT Tue aftn with some convection
along and south of it while the north is suppressed. Latest
guidance indicates a trailing short wave Wed sets off convection
across the CWA again as lower levels don't really dry out in the
wake of the front and moisture is available.
Updated earlier to lower pops west and south this morning and
across the north this aftn. Latest hi res guidance is now showing
convection across our WY zone this aftn as well as west of CDC so
will update again to add pops back into these areas.
&&
.AVIATION...Southeast winds at the SLC terminal will shift to the
northwest between 19Z and 21Z.
&&
.SLC WATCHES/WARNINGS/ADVISORIES...
UT...Fire Weather Watch from Monday afternoon through Monday evening
for UTZ497.
WY...None.
&&
Wilensky
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 301 AM MDT Sun Aug 13 2017 UTZ001>016-019>021-517-518-WYZ021-141300- 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- 301 AM MDT Sun Aug 13 2017 This Hazardous Weather Outlook is for the western two thirds of Utah and southwest Wyoming. .DAY ONE...Today and Tonight Thunderstorm coverage will decrease beginning today with drier air moving into the region from the west. A few of these may produce strong gusty/erratic winds east of Interstate 15. .DAYS TWO THROUGH SEVEN...Monday through Saturday Gusty southwest winds will develop Monday ahead of a cold front. Hazardous fire weather conditions will be possible Monday across the western valleys. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. Rogowski/Traphagan 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 Cedar City radar (KICX), 80 km away, was scanning. The volume nearest the first event began at 19:01 UTC.
2 hail, 1 thunderstorm wind. Local standard time, as filed.
An outflow from a thunderstorm south of St. George caused damage near the Red Cliffs Mall. Eight trees, 5 to 12 inches in diameter, were uprooted by these strong winds.
A member of the public reported dime-sized hail near Interstate 15 and 7200 South.
Nickel-sized hail was reported near Price.
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, August 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: 720462, 718999, 719000.