846
FXUS65 KSLC 102202
AFDSLC

Area Forecast Discussion
National Weather Service Salt Lake City UT
402 PM MDT Fri May 10 2024

.SYNOPSIS...An area of low pressure will remain over the region
through Saturday, keeping showers and thunderstorms in the
forecast for much of Utah. Higher pressure builds into the region
through the weekend, bringing a warming and drying trend to Utah
and southwest Wyoming into early next week. Thereafter, there is
potential for a storm system to bring another round of wetter and
cooler conditions to the region.

&&

.SHORT TERM (Through 12Z/6AM Sunday)...An upper level low remains
parked over the Great Basin region, bringing afternoon showers
and thunderstorms over the area. Easterly winds aloft remain in
place across northern Utah, however, previously strong winds in
the typical downsloping areas have subsided. That said, with the
easterly component to the wind lingering, should continue to see
isolated wind gusts to around 30 mph near canyons on the northern
Wasatch Front.

With the low lingering over the region, general instability tied
to the mid-level cold core will help to maintain showers and
thunderstorms over Utah during the heating hours. As of this
afternoon, the best instability and moisture availability exists
across the southern half of Utah, and thus have been seeing the
greatest coverage of showers and thunderstorms from Provo
southward and the central mountain spine westward. With limited
shear, developing showers have been very short lived with limited
threat of hail, however, have been seeing isolate gusts of 30+
mph. These showers will decrease in coverage as we lose heating
later this evening.

Tomorrow, the low remains in place over the region, however, an
eastward shift in the center of the low is expected. Another round
of showers and thunderstorms are expected during the afternoon
hours, with the primary focus being over the high terrain and
downwind valley areas. Steering flow will gradually shift from a
northeasterly flow (favoring southwest progression of storms) to a
north to northwest flow by the mid-to-late afternoon (favoring
south to southeast progression). The steering flow later tomorrow
afternoon will begin to favor showers potentially progressing
into more flash flood prone basins (i.e. Paria River Basin). While
limited deep moisture availability exists (PWAT values less than
0.5 inches), can`t rule out an isolated shower producing moderate
to heavy rainfall over a flashy drainage.

.LONG TERM (After 12Z/6AM Sunday)...By the beginning of the long-term
forecast period, the upper low will have already (finally!) made its
way east into Colorado, while high pressure builds into the Great
Basin. Utah will be under a north-northeast flow aloft for much of
the day Sunday, with a warming and drying trend. That said, isolated
to locally scattered convection remains possible across the higher
terrain Sunday afternoon. Temperatures will return to above-normal
values.

Heading into Monday, zonal flow will develop over Utah as a
shortwave trough grazes by to the north. This general pattern is
reflected on the majority of global ensembles. A few showers remain
possible with the trough skirting the area, otherwise temperatures
will continue to trend warmer, given H7 temperatures ranging from +6
to +10C across Utah. Afternoon max surface temperatures will have a
good chance of reaching 80F in many valley locales (a 64% chance at
SLC per the NBM).

Thereafter, the pattern starts to amplify with a ridge building off
the West Coast. This would allow the next trough to drop into
northern Utah some time on Tuesday or Tuesday night, bringing
another round of precipitation along with cooler temperatures.
Depending on how much the pattern amplifies, the trough could
continue to impact Utah into Wednesday. For the latter part of the
week, there is more uncertainty based on cluster analysis of
ensemble solutions. The four clusters range from varying
amplifications the upstream ridge to a more zonal pattern over the
area. For the time being, the NBM is trending towards a generally
dry pattern with a gradual warming trend through the end of the
week.


&&

.AVIATION...KSLC...Largely northerly to northeasterly winds will
continue with gusts to 20kts through roughly 02z. Scattered showers
this afternoon will be capable of producing gusty and erratic winds
up to 25kts, with the most likely direction being out the east as
showers move off the terrain. There is also a 15% chance of
lightning.

.REST OF UTAH AND SOUTHWEST WYOMING...Scattered showers and
thunderstorms capable of producing gusty and erratic outflow winds
will continue until roughly 01-03z, mainly across areas south of
KENV-KOGD-KEVW and especially along higher terrain. Largely light
winds are expected overnight, aside from some residual easterly
canyon winds along the Wasatch Front with gusts to 25 mph at canyon
entrances.

&&

.FIRE WEATHER...An area of low pressure will linger over the southern half of Utah
through tomorrow, keeping general instability draped over the
area. Lower level moisture and instability will bring a higher
likelihood of showers and thunderstorms over the high terrain from
about the Salt Lake area southward through the Arizona border,
with higher likelihood of wetting rains across the central and
southern Utah mountains while the northern Utah mountains will
have a much lower probability of wetting rains. Humidity will stay
more moderated through this period, however, a warming and drying
trend is expected through about Monday. Thereafter, there is
potential for a cooler and wetter storm system to move through
from Tuesday through Wednesday. That said, there remains some
uncertainty on the details.

&&

.SLC WATCHES/WARNINGS/ADVISORIES...
UT...None.
WY...None.
&&

$$

SHORT TERM...Webber
LONG TERM...Cheng
AVIATION...Cunningham
FIRE WEATHER...Webber

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