Severe Thunderstorm Warning 11, NWS Salt Lake City, UT

Area Forecast Discussion
National Weather Service Salt Lake City UT
854 AM MDT Thu Jun 6 2019

.SYNOPSIS...
High pressure aloft over the Utah today will shift east ahead of
an approaching cold Pacific trough schedule to reach the area
early this weekend. A strong cold front will sweep through the
region Friday into early Saturday, bringing much colder
temperatures to the state this weekend.

&&

.DISCUSSION...
A trough currently will make its way into the Pacific Northwest
today, with the majority of stronger height falls remaining to our
northwest.

The approach of the Pacific trough axis will elevate the wind
field. This will favor increasing shear across northern Utah
today which when combined with moderately significant instability
due to anomalously high Precipitable Water values, will bring the
potential for strong to severe thunderstorms through this evening.
The greatest threat appears to be damaging winds due to the
increase in wind field, high LCL, and dry boundary layer yielding
elevated DCAPE. This is also indicated by the full suite of
Convective Allowing Models. Copious small hail (potential
accumulation) and lightning are also concerns.

&&

.PREVIOUS DISCUSSION...
An unseasonably cold upper level trough remains just off the
Pacific Northwest/BritCol coast early this morning. This trough
will track east across the northern half of the western CONUS
through Saturday evening. The associated surface cold front will
enter far northwest Utah early Friday, then sweep through all but
extreme southern Utah by early Saturday. Much colder temperatures
will trail the front for the upcoming weekend.

A weakening vorticity max currently over northeast Nevada will
track east-northeast across northern Utah this morning. Recent
satellite and radar imagery indicate isolated convection ahead
of the approaching vorticity max. Convection will likely persist,
if not expand a bit in areal coverage as this weak dynamic
feature moves through the favorably moist air mass across
northern Utah this morning.

Looking at the potential for stronger convection forming again
across the north later this afternoon through this evening. A
trailing secondary shortwave will reach northwest Utah by late
afternoon. Ahead of this feature increasing moisture (PWAT values
0.85" - 1.00") along with steepening lapse rates will create a
favorable environment for deep convection. Increasing speed and
directional shear late this afternoon and evening could spawn
strong, or even isolated severe, thunderstorms across far
northwest Utah late this afternoon through around mid-evening.

The cold front associated with the passing upper trough will reach
far northwest Utah early Friday, then surge southeast during the
day supported by fairly strong low-level cold advection.
Precipitation associated with the frontal boundary will be
somewhat limited as the best mid-level cold air and dynamic
support from the passing upper trough will remain well to the
north of the forecast area.

Dry and rather cold air will followed the cold front into all but
extreme southern Utah this weekend. Temperatures will drop 15 to
25 degrees below Friday's highs Saturday, then only show modest
warming on Sunday. Overnight lows will also be substantially
colder due to clear skies and low humidities. Will have to watch
for cold temperatures affecting agricultural operations on Sunday
morning.

Benign weather with warming temperatures will be the theme for
much of next week. Dry northwest flow aloft will develop over the
Western US downstream of a ridge building along the West Coast.
This ridge will gradually weaken as it moves inland, but still
allow for a notable warming trend through the middle of the week
and quiet weather conditions for our area. Daytime highs will
start out the work week around normal, then climb to around 5
degrees above normal by later in the week (which could then rival
tomorrow for the warmest temperatures yet this year).

The ridge will dampen by later in the week as models (both
deterministics and ensemble means) depict a shortwave trough
drifting through westerly flow aloft and moving through the Great
Basin by the end of the workweek and into next weekend. If it
materializes, this would bring moderated temperatures and a chance
of showers/thunderstorms, especially to typical convective initiation
locations (i.e. most of the higher terrain).

&&

.HYDROLOGY...
With much warmer temperatures, snowmelt will accelerate at high
elevations. Waterways remain running high, cold and swift.
Exercise caution near waterways, and keep a close eye on children
and pets.

&&

.AVIATION...
VFR conditions are expected at the SLC terminal today. Southeast
winds will gradually increase through the day before shifting to
the northwest after 02z. Afternoon thunderstorm chances will
increase across northern Utah this afternoon, with good chances
the terminal will see activity, and may result in gusty erratic
winds at the terminal. A cool front passage between 23Z and 02Z
may affect the wind shift and become light and variable.

&&

.FIRE WEATHER...
Breezy with low RH expected for most valleys today, and moreso
Friday ahead of the next cold front.

ERC values remain below the 50th percentile, but are rising
across the state.

A warming and drying trend continues with increasingly gusty
southwest flow. A cold front will cross the state from northwest
to southeast Friday and Friday night, bringing cooler temperatures
to the region through the weekend.

Isolated to scattered showers and thunderstorms today, some may
be severe with copious lightning, very gusty/erratic winds, and
accumulating hail. Friday and Friday night, showers will mainly
affect northern Utah.

A warming and drying trend is forecast beginning Sunday and
extending through at least the middle of next week.

&&

.SLC WATCHES/WARNINGS/ADVISORIES...
UT...None.
WY...None.
&&

PUBLIC...10/Conger/Van Cleave
AVIATION...Dewey
FIRE WEATHER/HYDROLOGY...10

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
857 AM MDT Thu Jun 6 2019

UTZ001>016-019>021-517-518-WYZ021-071500-
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-
857 AM MDT Thu Jun 6 2019

This Hazardous Weather Outlook is for the western two thirds of
Utah and southwest Wyoming.

.DAY ONE...Today and Tonight

Scattered showers and thunderstorms will move through the
region today. There is a Slight Risk for Severe Thunderstorms
across Northern Utah. The strongest storms will bring the threat
of damaging winds, accumulating hail and copious lightning. Stay
aware of the threat for dangerous thunderstorms today.

With much warmer temperatures, snowmelt will accelerate at high
elevations. Waterways remain running high, cold and swift.
Exercise caution near waterways, and keep a close eye on children
and pets.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday

A strong cold front will cross Utah from northwest to southeast
on Friday. Gusty south winds ahead of this front will shift to
the northwest and remain elevated behind the front.

Much colder temperatures will follow the front for the weekend.
Temperatures Saturday will be 15 to 25 degrees colder than
Friday's readings, with the coldest temperatures across the
northern portion of the outlook area. Temperatures will warm on
Sunday, but still remain well below early June norms.

.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

Special Weather Statement
National Weather Service Salt Lake City UT
159 PM MDT THU JUN 6 2019

UTZ005-062045-
Great Salt Lake Desert and Mountains UT-
159 PM MDT THU JUN 6 2019

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHWESTERN BOX ELDER AND
NORTHWESTERN TOOELE COUNTIES UNTIL 245 PM MDT...

At 158 PM MDT, National Weather Service Doppler radar indicated a
strong thunderstorm near Wendover...moving northeast at 30 mph.

Half inch hail and winds in excess of 40 mph will be possible.

Locations impacted include...
Wendover and Bonneville Salt Flats.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If threatening weather approaches, take shelter in a sturdy building.

This storm may intensify, so be certain to monitor local radio and
available television stations for additional information and possible
warnings from the National Weather Service.

&&

A severe thunderstorm watch remains in effect until 1100 PM MDT for
northern Utah.

LAT...LON 4087 11404 4107 11366 4038 11365 4024 11404
TIME...MOT...LOC 1958Z 235DEG 27KT 4066 11409

Bonnette

Special Weather Statement
National Weather Service Salt Lake City UT
209 PM MDT THU JUN 6 2019

UTZ005-062100-
Great Salt Lake Desert and Mountains UT-
209 PM MDT THU JUN 6 2019

...SIGNIFICANT WEATHER ADVISORY FOR WEST CENTRAL BOX ELDER COUNTY
UNTIL 300 PM MDT...

At 209 PM MDT, National Weather Service Doppler radar indicated a
line of strong thunderstorms 8 miles east of Montello...moving
northeast at 40 mph.

Half inch hail and winds in excess of 40 mph will be possible.

Locations impacted include...
Lucin.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If threatening weather approaches, take shelter in a sturdy building.

This storm may intensify, so be certain to monitor local radio and
available television stations for additional information and possible
warnings from the National Weather Service.

&&

A severe thunderstorm watch remains in effect until 1100 PM MDT for
northern Utah.

LAT...LON 4153 11405 4171 11367 4120 11366 4102 11404
TIME...MOT...LOC 2009Z 237DEG 33KT 4127 11403

Bonnette

Special Weather Statement
National Weather Service Salt Lake City UT
232 PM MDT THU JUN 6 2019

UTZ005-062100-
Great Salt Lake Desert and Mountains UT-
232 PM MDT THU JUN 6 2019

...SIGNIFICANT WEATHER ADVISORY FOR NORTHWESTERN BOX ELDER COUNTY
UNTIL 300 PM MDT...

At 232 PM MDT, National Weather Service Doppler radar indicated a
strong thunderstorm 28 miles south of Oakley Reservoir...moving
northeast at 35 mph.

Winds in excess of 40 mph will be possible.

Locations impacted include...
Lynn, Grouse Creek and Etna.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If threatening weather approaches, take shelter in a sturdy building.

This storm may intensify, so be certain to monitor local radio and
available television stations for additional information and possible
warnings from the National Weather Service.

&&

A severe thunderstorm watch remains in effect until 1100 PM MDT for
northern Utah.

LAT...LON 4170 11367 4151 11405 4154 11405 4154 11404
      4186 11404 4199 11378 4199 11367
TIME...MOT...LOC 2032Z 227DEG 31KT 4176 11402

Bonnette

Special Weather Statement
National Weather Service Salt Lake City UT
250 PM MDT THU JUN 6 2019

UTZ005-062130-
Great Salt Lake Desert and Mountains UT-
250 PM MDT THU JUN 6 2019

...SIGNIFICANT WEATHER ADVISORY FOR WESTERN BOX ELDER AND
NORTHWESTERN TOOELE COUNTIES UNTIL 330 PM MDT...

At 250 PM MDT, National Weather Service Doppler radar indicated
strong thunderstorms along a line extending from 20 miles west of
Park Valley to 26 miles east of Montello...and moving east at 35 mph.

Winds in excess of 40 mph will be possible.

Locations impacted include...
Park Valley and Rosette.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If threatening weather approaches, take shelter in a sturdy building.

These storms may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

&&

A severe thunderstorm watch remains in effect until 1100 PM MDT for
northern Utah.

LAT...LON 4196 11320 4121 11318 4093 11403 4122 11404
      4131 11377 4175 11378
TIME...MOT...LOC 2050Z 247DEG 28KT 4171 11370 4122 11368

Bonnette

Special Weather Statement
National Weather Service Salt Lake City UT
301 PM MDT THU JUN 6 2019

UTZ003>005-008-015-062145-
Wasatch Mountains South of I-80 UT-
Great Salt Lake Desert and Mountains UT-Southern Wasatch Front UT-
West Central Utah UT-Salt Lake and Tooele Valleys UT-
301 PM MDT THU JUN 6 2019

...SIGNIFICANT WEATHER ADVISORY FOR NORTHEASTERN JUAB...SOUTHWESTERN
UTAH AND SOUTHEASTERN TOOELE COUNTIES UNTIL 345 PM MDT...

At 301 PM MDT, National Weather Service Doppler radar indicated a
strong thunderstorm 16 miles west of Elberta, or 24 miles northwest
of Nephi...moving northeast at 10 mph.

Penny size hail and winds in excess of 40 mph will be possible.

Locations impacted include...
Payson, Eagle Mountain, Santaquin, Salem, Elk Ridge, Woodland Hills,
Rocky Ridge, Benjamin, Spring Lake, West Mountain, Elberta, Lake
Shore, Genola, Goshen, Eureka, Jericho, Tintic Junction, Little
Sahara State Park and Lofgreen.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If threatening weather approaches, take shelter in a sturdy building.

This storm may intensify, so be certain to monitor local radio and
available television stations for additional information and possible
warnings from the National Weather Service.

If on or near Utah Lake, get out of the water and move indoors or
inside a vehicle. Remember, lightning can strike out to 10 miles
from the parent thunderstorm. If you can hear thunder, you are close
enough to be struck by lightning. Move to safe shelter now! Do not
be caught on the water in a thunderstorm.

&&

A severe thunderstorm watch remains in effect until 1100 PM MDT for
central and northern Utah.

LAT...LON 3962 11215 3985 11255 4032 11214 4002 11161
TIME...MOT...LOC 2101Z 224DEG 10KT 3987 11224

Bonnette

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
303 PM MDT THU JUN 6 2019

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0230 PM     TSTM WND GST     10 ENE WENDOVER         40.78N 113.83W
06/06/2019  M56.00 MPH       TOOELE             UT   MESONET

            A 56 MPH WIND GUST WAS REPORTED AT THE BONNEVILLE SALT
            FLATS MESONET STATION.

&&

MT