499
FXUS65 KPIH 162019
AFDPIH

Area Forecast Discussion
National Weather Service Pocatello ID
219 PM MDT Tue Jul 16 2024

.SHORT TERM...Today through Wednesday Night.
The heat is back on today and tomorrow as highs continue to slowly
rise. Many will go from the upper 80s to low and mid 90s this
afternoon to more widespread low to mid 90s on Wednesday afternoon.
Even though high pressure is generally in control, it has slipped
just far enough to our southeast and will be flattened just a bit
more by a shortwave trough moving into the PNW tomorrow. This will
allow some monsoonal moisture to creep into our area. The best
chance, about a 10 to 20 percent chance, for that today will be
along the Wyoming state line. Wind gusts today are expected to be
"typical" afternoon gusts around 15 to 20 mph through the eastern
Magic Valley and Snake Plain. Gusts associated with any convection
we can get going would be closer to the 30 to 40 mph range. As for
continued haze across the area and any smoke impacts, the HRRR is
showing reduced visibility tonight down to about 3 to 7 miles
through parts of the Wood River valley, eastern Magic Valley, and
lower Snake Plain from the Bench Lake fire. The NAM and NBM don`t
seem to be picking up on this at all, but the HRRR generally does a
bit of a better job in this aspect. So, we will see how that pans
out overnight to get a better feel for model verification (and a
reality check on my own bias). The potential for isolated afternoon
convection continues on Wednesday for parts of the Eastern
Highlands, but also for portions of the Magic Valley, South Hills,
and Central Mountains. These will likely be dry storms again, as
monsoonal moisture is quite limited, but convective-related wind
gusts will be in the 35 to 45 mph for many. This may push closer to
50 to 55 mph in parts of the Magic Valley and South Hills.
AMM

.LONG TERM...Thursday through Tuesday.
The long term pattern remains relatively unchanged. Ensemble
clusters maintain ridge of high pressure over the Great Basin
throughout. Weak moisture rotating around the ridge may provide
for isolated mainly higher elevation thunderstorms each day.
Forecast temperatures remain stable, still hot but generally below
our recent excessive heat event. There may be a few zones that
flirt with Heat Advisory conditions, but relatively cool low
temperatures below 65 degrees MOST areas will mitigate some of the
potential.
DMH


&&

.AVIATION...There is still a minor potential for convection, with
the main threat until about 02Z for KDIJ, and even less so for KIDA.
Outflow potential to about 30kts. That said, not sure there is
enough confidence to include VCTS at either location. Some of the
high res model solutions also depict weak overnight convection.
Again, not enough confidence to include any mention at this time.
The main overarching concern will be smoke impacts. Satellite
imagery shows widespread swath of smoke/haze from upstream
wildfires. HRRR Smoke has been persistent and robust with smoke
influence impacting KSUN overnight under downslope northerly flow
regime. Have brought KSUN down to at least MVFR VSBY overnight, with
expectations for occasional IFR. KBYI also likely to see occasional
obscuration overnight, but kept VSBY at VFR. KPIH and KIDA will also
have potential, but expectations remain VFR at this time.
DMH


&&

.FIRE WEATHER...Temperatures will continue to slowly climb through
the rest of the week and at least a 10 to 20 percent chance of
afternoon convection will persist. These chances will be mostly
confined to parts of the Eastern Highlands along the Wyoming
border. These storms are expected to be dry storms with the
potential for convective wind gusts of 30 to 40 mph. By Wednesday
afternoon, parts of the Magic Valley, South Hills, and Central
Mountains will join in on the isolated convection. These will
likely be dry storms once again, though wind gusts with these will
range from 35 to 45 mph with the potential for strong gusts of 50
to 55 mph in the Magic Valley and South Hills. The SPC and GACC
have also highlighted portions of fire weather zones 422, 425,
427, 475, and 476 tomorrow for the isolated dry thunderstorm
chances mentioned above. In the second half of the week, we will
keep around the chance for isolated convection each afternoon.
Otherwise, synoptic wind gusts will be in the 15 to 20 mph range
each day with min RHs ranging from mid teens to mid 20s.
AMM


&&

.PIH WATCHES/WARNINGS/ADVISORIES...
None.
&&

$$