Area Forecast Discussion
Issued by NWS Salt Lake City, UT

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FXUS65 KSLC 231023
AFDSLC

Area Forecast Discussion
National Weather Service Salt Lake City UT
423 AM MDT Fri Jun 23 2017

.SYNOPSIS...A generally dry west to northwest flow aloft will exist
across Utah today and tomorrow. Strong high pressure aloft will
return to the region late in the weekend. A brief surge of moisture
will move through the area Monday, followed by a dry westerly flow
aloft by the middle of the week.

&&

.SHORT TERM (Through 12z Sunday)....Heights continue to lower
slightly across the northern 2/3rds of the area as the predominant
desert southwest High continues to bulge north and west from AZ
across NorCal, this in response to northern branch energy diving SE
into the northern Plains. A modest N-S MSLP gradient remains in
place across the entirety of the area this morning beneath an
increasingly stable and dry northwesterly flow aloft. Little change
to the broad scale pattern is expected through the end of the long
term period with temps across the north remaining near seasonal, and
well above average across the far southwest (more influence from
ridge there). An excessive Heat Warning remains in place for Dixie
through Sunday as minimal changes to sensible weather will occur.

Have a mention of areas of smoke from the southern UT mountains
south to Kanab, then east to the southern half of Lake Powell due to
the extensive smoke plume extending from the Brian Head Fire. As
minimal change is expected to the wind fields the next few days,
have carried a similar placement through the end of the short term.

.LONG TERM (After 12z Sunday)...High pressure is progged to build
back into the Great Basin on Sunday leading to warmer conditions
across northern and central Utah. This warming trend will continue
into Monday as southwesterly flow starts to develop with the ridge
axis shifting into eastern Utah. However, midlevel moisture
spreading into the area will lead to increased cloud cover and a
chance for convective development especially by Monday afternoon.

Although going Excessive Heat Warning for Dixie currently continues
through Sunday, a case can be made for a possible extension through
Monday given continued hot temperatures. Will address this within
the next couple of days.

A weak shortwave trough sagging into northern Utah late Monday into
Tuesday will push a shallow cold front into the area. Lingering
moisture could continue to allow for some convection across northern
Utah, but overall a drier airmass will spread into the area. After
that, the pattern will remain nearly zonal with embedded weak waves
which will continue to keep a somewhat cooler airmass in place
through the middle of the week.

&&

.AVIATION...VFR conditions under clear skies will continue
at the SLC terminal through the valid TAF period. Winds will remain
rather light and variable this morning, transitioning to a northerly
flow by 16-18z.

&&

.FIRE WEATHER...A dry west to northwesterly flow aloft will remain
in place across the district through the weekend, but wind trends
are expected to decrease a little each day. Hot and dry conditions
will be maintained across the south and east where a Haines of 6
will remain for the next several days. Breezy winds can be expected
across both the southern UT mountains and namely the prone downslope
areas across the interface of the central mountains and castle
country this afternoon, but gusts are expected to remain below
critical thresholds as a whole. In general trends point towards
lighter winds over the weekend becoming more dominated by diurnal
trends. Strong solar is expected under clear skies through the
weekend.

The areal expanse of Haines 6 values will expand north late weekend
into early next week coupled with another strong warming trend
Sunday through Monday. A week system will likely bring isolated
showers namely northern portions of the district Monday night and
Tuesday.

&&

.SLC WATCHES/WARNINGS/ADVISORIES...
UT...Excessive Heat Warning until 10 PM MDT Sunday for UTZ019.

WY...None.
&&

$$

Merrill/Cheng

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http://weather.gov/saltlakecity

For frequently asked questions about the Area Forecast Discussion
visit...
http://weather.gov/saltlakecity/general/afd_faqs.php



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