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Area forecast discussion 
National Weather Service Salt Lake City Utah
439 PM MDT Tuesday Jul 29 2014

Synopsis...a very moist air mass will remain over the area through
early Wednesday. A slow drying trend will take hold beginning
Wednesday as high pressure aloft builds across the interior west.


Discussion...very moist airmass remains in place across Utah this
afternoon with precipitable water values around 1.25" across much
of the state. In addition...SBCAPE values across Utah are
generally 500-1000 j/kg late this afternoon. Two upper level
circulations are interacting with this very moist airmass to bring
showers and thunderstorms to the state. One upper level
circulation is moving slowly east across northern Utah this
afternoon. This disturbance brought numerous showers and
thunderstorms to northern Utah today...but coverage is diminishing
late this afternoon as the upper level lift associated with the
leading edge of the circulation moves east. However...with
lingering instability in place and the back edge yet to pass
through region...will keep mention of scattered thunderstorms into
the evening hours. A second circulation is moving through central
Utah and it is associated with numerous showers and thunderstorms
across the central portion of the state. Behind this wave a little
more stable air is filtering into southwest Utah which will lead
to a decrease in the coverage of storms this evening. Any storms
that develop this evening across the state have the potential to
produce heavy rain. Storms have been very efficient rain producers
and anticipate that to continue through the evening.

Flow aloft becomes northwest over the state on Wednesday on
backside of departing upper level disturbance. Airmass dries out a
bit...but precipitable water values still remain up near an inch.
Although there will not be the organized was the
case today....anticipate isolated valley convection and scattered
convection over the high terrain during the afternoon and evening
hours. Despite the downward trend in precipitable water
values...some storms will be capable of producing heavy. In
addition...storms in southern Utah will tend to move south which
raises the potential for down drainage movement. Temperatures
will rebound a bit on Wednesday as cloud cover will be less
extensive across the state.

Upper level ridge then builds in for the remainder of the week
with a slow warming trend expected through the weekend. Medium
range models continue to show weak disturbance moving over the top
of the ridge Thursday night into Friday bringing a threat of
showers and thunderstorms to northern Utah. Anticipate a drying
trend for the north over the weekend with isolated convection in
the south where the deeper moisture is confined.


Aviation...VFR conditions are expected to prevail through the
taf period at the slc terminal. Winds should stay generally
southerly through the night but will be light and variable at
times through about 02z. Showers could cross the terminal at times
after about 02- 04z tonight into Wednesday morning. There is a 20
percent chance of brief MVFR visibilities in heavy rain if a shower
passes directly overhead. Gusty erratic winds could also accompany


Fire weather...monsoonal moisture remains over the district
today...resulting in numerous showers and thunderstorms. Any storms
that develop through the evening will likely produce wetting
rainfall. The district will see a slow drying trend beginning
tomorrow. However...more than enough moisture will remain in place
for isolated to widely scattered afternoon convection with some
lingering into the overnight hours. Under the influence of high
pressure...winds will be generally light over the next few days
across the district outside of thunderstorms.


Slc watches/warnings/advisories...


fire weather...traphagan

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