284
FXUS65 KPIH 270852
AFDPIH

Area Forecast Discussion
National Weather Service Pocatello ID
252 AM MDT Mon May 27 2024

.SHORT TERM...Today and Tuesday
Pleasant weather expected for your Memorial Day across eastern Idaho
as high pressure continues to amplify over the region. We should see
mostly clear skies, light winds with temperatures near seasonal
norms. This means lower to middle 70s across the Snake Plain and
Magic Valley with mountain zones in the mid to upper 60s. Hi-res
CAMs show basically very little chance of see any precip today and
the forecast agrees accordingly.

On Tuesday, we`ll see widespread 80s for the first time this year as
high pressure reaches it`s maximum intensity over the area around
mid day. Lower 80s will likely be realized into the upper Snake
Plain and certainly into the lower Snake and Magic Valley. Mountain
zones will see lower to middle 70s as well so certainly one of the
warmer days we`ve seen in quite some time. A trough will begin to
dig into the Pacific NW during the day and this feature should help
to reintroduce PoPs back into the forecast during the afternoon and
evening hours. Coverage looks scattered in nature with best coverage
likely across the central mountains. Given the warm temperatures,
thunderstorms can be expected some of which could be strong. The
Storm Prediction Center has a "marginal risk" designation sneaking
into the the northwestern most portion of the CWA (around Stanley)
but we`ll see how hi-res guidance handles things over the next 24-36
hours. McKaughan

.LONG TERM...Wed through Sun night
Clusters indicate an low confidence forecast, if you need completely
dry conditions. The first day has a trough approaching from the
west, but has not yet reached the forecast area really by Wed
afternoon. For Thu, the guidance is split evenly between solutions
that keep the trough either farther north (not much of a factor)
and overhead (wetter, more unstable, cooler). Some solutions slow
down the eastward movement for Fri, but they are a minority with
most having moved the trough far enough east to warm and dry. By
the coming weekend, an upper level ridge axis is over eastern
Idaho; it`s just a matter of how amplified the axis is. Only 14
percent have a low- amplitude trough over the northern portions of
the forecast area on Sun afternoon. So would expect a dry and
warm weekend.

Temperatures are knocked back down on Thu with the trough, with
widespread afternoon highs in the 60s, even in Stanley. Conditions
are slow to warm with a west northwest airflow, but stronger warming
finally kicks on the weekend, with afternoon highs in the 70s for
the lower elevations in the Snake River plain/eastern Magic Valley,
to the potential for reaching 80 degrees at lower elevations on Sun.
Even Thu night should have low temperatures above Frost Advisory
thresholds.

The approach of the trough indicates Wed late afternoon to evening
to have solid chances of reaching Wind Advisory conditions, and
breezy to windy conditions Thu. Fri through the weekend appears to
be much calmer. Messick


&&

.AVIATION...
VFR conditions expected through the forecast period with high
pressure in control across the region. Winds will be much lighter
today, generally 10 knots or less, throughout the day. Skies will be
mostly clear allowing for near perfect flying conditions throughout
eastern Idaho. McKaughan

&&

.FIRE WEATHER...
Dry and sunny conditions through Wed means that temperatures will
finally feel summer-like on Tue as many of the lower elevations
should be crossing the 80-degree F threshold that afternoon, for
the first time since 2023. Until Tue, minimum humidity should stay
in the upper teens and 20s, even higher in the eastern highland
mountain tops. With the approaching trough, the humidity spikes
upward for both Wed and Thu. Very windy conditions are possible
with this trough on Wed prior to its arrival. Thunderstorms will
be around for Tue and Wed with strong outflow winds possible over
the Salmon-Challis NF both days. Messick

&&

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

$$