143
FXUS65 KSLC 060951
AFDSLC

Area Forecast Discussion
National Weather Service Salt Lake City UT
351 AM MDT Thu Jun 6 2024

.SYNOPSIS...An early season heat wave will impact the area through
the work week, with record-challenging temperatures anticipated
today into Friday. As the ridge flattens Friday into the weekend,
the warming trend will curb and some moisture will move into the
area, increasing the threat of convection. The threat of showers
and thunderstorms will continue into early next week.

&&

.SHORT TERM (Through 12Z Saturday)...Strong high pressure is in
place over the region this morning, with the axis centered over
Utah. As a result, the forecast area is cloud free due to the dry
and stable airmass. The warming trend of the last couple of days
will continue, with high temperatures forecast to run in excess of
15F above seasonal normals across the area. This early season heat
wave will bring dangerous conditions to the valleys of southern
and eastern Utah, where a suite of Excessive Heat Warnings and
Heat Advisories go into effect at 11am.

By Friday morning, the ridge axis will have moved east of the area
into Colorado, putting Utah and southwest Wyoming under a west to
southwest flow aloft. A trough moving across southwest Canada will
pass just far enough south to flatten the ridge some, and this
combination will allow some moisture to come back northward into
the area. Thus, the area will see the return of high based
convection capable of producing gusty and erratic winds, though
coverage will initially be fairly isolated. The guidance has
steadily sped up the timing of these events over the last few
runs. While previous forecasts showed the warming trend continuing
into Friday, it is looking increasingly likely that Friday
afternoon`s temperatures will be similar to today, if not a couple
of degrees less warm in some spots given increasing clouds.
Still, temperatures will remain quite unseasonably warm,
warranting another day of heat headlines for the southern Utah
valleys.

.LONG TERM (After 12Z Saturday)...A mostly dry and hot pattern
will continue through the long term period. However, the ridge that
is responsible for the heat will flatten again on Saturday,
thanks to a shortwave moving across northern Utah, allowing
temperatures to cool a couple of degrees. Temperatures will still
remain ~10 degrees above normal across most of the region. This
shortwave won`t have much synoptic support, and environmental
shear/instability/moisture will be lacking. So if any storms are
able to form they will likely be confined to the terrain of the
central and northern mountains with a focus over the Uintas.

Similar surface conditions are expected on Sunday, but flow aloft
will transition to a southwesterly component ahead of a trough
moving onshore. This will help to advect more mid and upper level
moisture into the Great Basin with increasing cloud cover. Given
better shear/instability/moisture on Sunday expect a slightly higher
chance of afternoon convection, particularly over the terrain.
Soundings are highlighting inverted V profiles, indicating drier
conditions near the surface. Given greater winds aloft, the
potential for momentum transfer to the surface will be elevated with
any storms that do form, resulting in gusty and erratic winds.

This trough will pass by to the east on Monday with temperatures
cooling a few degrees on Monday and Tuesday with mostly dry
conditions prevailing as a low amplitude ridge stays positioned
across the Rockies. Guidance is in good agreement that by the end of
next week a cutoff low off the southern California coast will begin
to meander inland. This will prevent the ridge from amplifying,
although temperatures will remain above normal, and provide more
precipitation chances.

&&

.AVIATION...KSLC...VFR conditions will prevail for the KSLC
terminal. Expect dry conditions with a few high clouds and light
diurnally driven winds. Southerly winds overnight will transition to
a northerly lake breeze during the day.

.REST OF UTAH AND SOUTHWEST WYOMING...VFR conditions will prevail
across all terminals. Expect mostly clear skies, dry conditions, and
light variable winds. Isolated afternoon convection is possible near
the Nevada border that could produce some gusty and erratic winds.

&&

.FIRE WEATHER...High pressure will continue to build over Utah
today, bringing dry and very hot conditions. High temperatures
will run up to 20F above seasonal normals both today and Friday,
resulting in some record challenging temperatures. The ridge axis
will move east of the area on Friday, allowing some moisture to
return to the area. This will bring the return of some high-based
showers and thunderstorms that will produce little rainfall,
bringing a threat of dry lightning and gusty winds. The threat of
showers and thunderstorms will continue into early next week, with
temperatures staying quite unseasonably warm.

&&

.SLC WATCHES/WARNINGS/ADVISORIES...
UT...Heat Advisory from 11 AM this morning to midnight MDT Friday
     night for UTZ121-122-128>130.

     Excessive Heat Warning from 11 AM this morning to midnight MDT
     Saturday night for UTZ123-124-131.

WY...None.
&&

$$

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

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