Special Weather Statement, NWS Salt Lake City, UT

Area Forecast Discussion
National Weather Service Salt Lake City UT
911 AM MDT Sun Jun 16 2019

.SYNOPSIS...A weak weather disturbance will keep a threat of showers
and thunderstorms over the area through Tuesday. Drier weather will
return for midweek. A cold front is expected to move into the area
late in the week.

&&

.DISCUSSION...A weakly defined trough is centered over the
southern California coast this morning. An associated vort max
ejecting out ahead of this system is currently making its way into
west central Utah and is allowing for some shower activity over
southwest Utah. Coverage of convection will continue to increase
through the afternoon, aided by daytime heating, as the wave
continues to work east. Focus of convection will remain over
central and southern Utah. Lower levels are on the dry side, so
there is a threat of gusty winds with any storms that develop.
Updated the forecast earlier to increase POPs slightly and expand
areal coverage. No additional updates planned.

The California low is expected to move little before closing off
tomorrow night/early Tuesday. West to southwest flow will continue
to draw moisture into Utah and southwest Wyoming and additional
ejecting shortwaves will provide instability, so expecting an
overall increase in coverage of convection tomorrow. Temperatures
will not change much, resulting in another day of maxes near
seasonal normals.

As a Pacific high builds, the California low is progged to weaken
on Tuesday, shifting the flow over the area to a more
northwesterly direction. One last piece of shortwave energy is
expected to cross northern Utah during the day Tuesday, but
overall coverage of convection will decrease, becoming more
focused over the higher terrain. The building ridge will provide
dry and warmer conditions for Wednesday. However, a grazing
Pacific Northwest system will bring a good cold front into at
least northern Utah, resulting in noticeably cooler temperatures
and perhaps some showers and thunderstorms.

&&

.HYDROLOGY...Recent and continued seasonably warm temperatures have
allowed for rapid snowmelt which has resulted in rises on area
streams and rivers. Most concerning continues to be the Duchesne
River which remains above flood stage near Myton, where a Flood
Warning remains in effect until midweek. Concern also exists for
Little Cottonwood Creek to approach flood stage through tomorrow
evening. A Flood Watch is in effect for Little Cottonwood.

&&

.AVIATION...A stable west-northwest flow aloft across northern Utah
will serve to maintain VFR conditions at the KSLC terminal through
the current TAF period. Light southeast winds will make the turn to
west, then northwest between 17z and 19z. Winds will return to the
southeast around 04z.

&&

.SLC WATCHES/WARNINGS/ADVISORIES...
UT...Flood Watch through Monday evening for UTZ003.

WY...None.
&&

Traphagan/Conger

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
555 AM MDT Sun Jun 16 2019

UTZ001>016-019>021-517-518-WYZ021-171300-
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-
555 AM MDT Sun Jun 16 2019

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

.DAY ONE...Today and Tonight

The Duchesne River between Hanna and Myton is expected to remain
above flood stage. Little Cottonwood Creek may approach flood
stage this evening.

Showers and thunderstorms will affect mainly southern and central
Utah. Brief gusty winds will be possible with some of the storms.

.DAYS TWO THROUGH SEVEN...Monday through Saturday

Showers and thunderstorms can be expected Monday and Tuesday.
Brief gusty winds will be possible with some of the storms.

Waterways will continue to run high, cold, and swift. Exercise
caution near waterways, and keep a close eye on children and pets.
The Duchesne River between Hanna and Myton is expected to remain
above flood stage through at least the first half of the week.
Little Cottonwood Creek may approach flood stage.

.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
221 PM MDT SUN JUN 16 2019

UTZ003>005-162115-
Great Salt Lake Desert and Mountains UT-Southern Wasatch Front UT-
Salt Lake and Tooele Valleys UT-
221 PM MDT SUN JUN 16 2019

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHWESTERN SALT LAKE...
NORTHWESTERN UTAH AND EASTERN TOOELE COUNTIES UNTIL 315 PM MDT...

At 220 PM MDT, National Weather Service Doppler radar indicated a
strong thunderstorm near Herriman, or 12 miles east of Tooele. This
storm was nearly stationary.

Nickel size hail and winds in excess of 40 mph will be possible.
Heavy rainfall and frequent lightning are also threats.

Locations impacted include...
West Jordan, South Jordan, Riverton, Herriman, Bluffdale and
Copperton.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Heavy rainfall is also occurring with this storm, and may lead to
localized flooding. Do not drive your vehicle through flooded
roadways.

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

&&

LAT...LON 4062 11204 4044 11191 4043 11203 4045 11205
      4043 11208 4043 11210 4053 11219
TIME...MOT...LOC 2020Z 235DEG 3KT 4048 11208

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