673
FXUS65 KSLC 082047
AFDSLC
Area Forecast Discussion
National Weather Service Salt Lake City UT
247 PM MDT Thu May 8 2025
.SYNOPSIS...High pressure will maintain trend conditions warmer
and drier through the first half of the weekend. Starting Sunday,
an approaching trough will bring more terrain based convection
across the north with strong southerly winds developing. This
trough will bring a cold front and wide spread precipitation by
early next week.
&&
.SHORT TERM (Through 12Z/6AM Saturday)...Isolated diurnal
convection, mainly across the terrain, will dissipate after
sunset as high pressure builds into the region. Dry conditions are
expected on Friday with highs running about 10-15 degrees above
normal. This will translate to upper 70s/low 80s across the
valleys outside of lower Washington county. Lower Washington
county temperatures will be in the low 90s.
.LONG TERM (After 12Z/6AM Saturday)...The broad ridge over Utah and
southwest Wyoming will start to make its way east during the day
Saturday as a trough approaches the Pacific coast. Winds will start
to increase out of the south on the back side of the ridge during
the afternoon, allowing for more efficient mixing. This will help to
usher in the warmest temperatures of the forecast period, with
temperatures averaging up to 20F above normal for this time of year.
There remains a medium chance that some northern valley locations
such as Salt Lake City will see their first reading of 90F or above
of the year.
Beginning Sunday, attention turns to that pattern changing trough,
which is expected to start to bring a cold front into northwest Utah
Sunday evening, through much of northern Utah during the day Monday,
and through the remainder of the area on Tuesday. The biggest impact
from this system may be pre-frontal winds, which given the tight
gradient along the front become strong and gusty for at least
western Utah Sunday into Monday and then more for southeast Utah on
Tuesday. Current guidance indicates at least a high chance of
advisory level winds for those wind prone areas, with a medium
chance of winds moving into stronger territory. The passage of the
front will also bring noticeably cooler temperatures, dropping maxes
to or below normal for this time of year. Guidance has been
consistent in showing less than impressive moisture associated with
the system, but still anticipate good coverage of showers, at least
for northern and central portions of the forecast area. In looking
at the ensemble cluster analysis, models are showing better than
usual consistency with regard to the timing and track of the system,
at least through Tuesday. Spread increases thereafter as to just how
quickly the system will exit the area, though most show it lingering
into day seven. There also remains noticeable spread with regard to
the strength of the trough, which would impact how strong winds get,
how much temperatures cool, and what the coverage of showers might
be. Will look for more consensus as the system approaches.
&&
.AVIATION...KSLC...The SLC terminal will see VFR conditions through
the evening with some scattered clouds. Northwest winds are expected
to return to the northwest between 03Z and 05Z.
REST OF UTAH AND SOUTHWEST WYOMING...VFR conditions are expected
through the evening across the area space with generally light and
terrain driven winds. Isolated showers will continue over the higher
terrain into the early evening, with a low chance of gusty and
erratic winds in the vicinity of any cells that develop.
&&
.FIRE WEATHER...High pressure building over the area will keep
conditions mostly dry, aside from some very isolated diurnal
driven convection on the terrain (<10% chance). Conditions will
also warm 10 to 20 degrees above normal. Mixing heights will be
more typical of those we see in the peak of the summer months.
By Sunday, a trough approaches from the PNW. This will lead to
strong southerly winds developing across the region with dry
surface conditions. Diurnal high-based convection will be possible
(30-40% chance) across northeast Utah on Sunday where some
enhanced lift from the approaching trough will exist. Winds stay
strong through Monday and Tuesday before the trough brings a cold
front with widespread precipitation by Tuesday afternoon and
evening.
&&
.SLC WATCHES/WARNINGS/ADVISORIES...
UT...None.
WY...None.
&&
$$
SHORT TERM...Mahan
LONG TERM...Traphagan
AVIATION...Traphagan
FIRE WEATHER...Mahan
For more information from NOAA`s National Weather Service visit...
http://weather.gov/saltlakecity
