710
FXUS65 KSLC 040929
AFDSLC

Area Forecast Discussion
National Weather Service Salt Lake City UT
329 AM MDT Tue Jun 4 2024

.SYNOPSIS...High pressure will build over the area through the end
of the work week, resulting in dry and increasingly hot
conditions. Unsettled weather may return for the weekend.

&&

.SHORT TERM (Through 12Z Thursday)...The cold front that moved
across northern Utah yesterday has moved into southern Utah this
morning, albeit in a rather weakened state. Associated
precipitation has ended, with just a shield of high clouds
remaining as one last shortwave rotates through the northwest flow
aloft.

Meanwhile, a broad ridge is making its way toward the
Pacific coast, and will expand into Utah and southwest Wyoming
later today. The ridge axis will eventually move over the state by
early Thursday, with conditions becoming dry and increasingly hot
as the ridge axis approaches. By Wednesday afternoon, looking at
maxes averaging around 10F above seasonal normals, with the heat
moving into dangerous levels for some locations in the long term
period. More details below.

.LONG TERM (After 12Z Thursday)...Unseasonably warm conditions
are forecast throughout southwest Wyoming and Utah later in the
week, with Thursday and Friday likely the warmest. A strong ridge
will expand throughout the west late in the week into the weekend,
with high pressure positioned near the Four Corners. The ridge axis
will be over Utah Thursday and extend into Canada. Valley high
temperatures will be in the upper 80s or low 90s near the Idaho
border, mid 90s for the urban corridor, and mid to upper 90s for
central valleys. Temperatures will get into 100s around Lake Powell.
As usual, lower Washington County will be the warmest, with highs
around 110F. As the ridge axis slides slightly downstream, that will
allow for shortwave energy within anticyclonic flow for some clouds
Thursday into Friday. The extremely warm, sunny day will be followed
by a warm night, with clouds keeping temperatures warmer than if it
were clear. Friday morning lows will be in the 60s for many valleys,
but could stay in the 70s for the Salt Lake Valley. Lows will only
drop to the mid 70s around Lake Powell and lower Washington County.
An Excessive Heat Warning is in effect Thursday around Lake Powell
and for lower Washington County.

Synoptic conditions will be largely similar Friday, with the biggest
difference of more clouds. Weak shortwave energy will push in from
the west to southwest. There will be isolated showers and
thunderstorms around terrain, but that will likely have minimal
effects on valley temperatures. Forecast highs are nearly identical
to Thursday, with some places likely to be slightly cooler and
others slightly warmer, largely depending on clouds. The Excessive
Heat Warning for portions of southern Utah lasts through the day.

There is good model agreement through the weekend and into the week
on much warmer than normal temperatures. The ridge will likely stay
in place, but not be as strong, as more shortwaves push in from the
west. Isolated to scattered showers and thunderstorms will primarily
be around terrain, as forcing will be limited with little moisture
and wind shear. Gusty, erratic outflow winds would be expected near
showers and thunderstorms.

&&

.AVIATION...KSLC...Northwest winds will last through the day, with a
transition to southeast winds around 03Z. Clouds will diminish
through the day, with low clouds around mountain terrain into the
afternoon.

.REST OF UTAH AND SOUTHWEST WYOMING...Low clouds, primarily around
the northern mountains, will diminish into the afternoon. Light
winds will last through the day with decreasing clouds.

&&

.FIRE WEATHER...As a Pacific Northwest storm system exits, a broad
Pacific high will build eastward over Utah. This will result in
dry and increasingly hot conditions through Friday. For southern
Utah, highs will approach record values by Friday afternoon. The
ridge is expected to weaken a bit for the weekend, bringing the
potential for some moisture and instability to return, though
uncertainty is high with regard to the details. Overnight recovery will
remain poor through the week across southern Utah, and become
increasingly poor across northern Utah through the week.

&&

.SLC WATCHES/WARNINGS/ADVISORIES...
UT...Excessive Heat Warning from 11 AM Thursday to midnight MDT
     Friday night for UTZ123-131.

WY...None.
&&

$$

SHORT TERM/FIRE WEATHER...Traphagan
LONG TERM/AVIATION...Wilson

For more information from NOAA`s National Weather Service visit...
http://weather.gov/saltlakecity