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000
FXUS65 KPIH 220846
AFDPIH

Area Forecast Discussion
National Weather Service Pocatello ID
246 AM MDT Thu Apr 22 2021

.SHORT TERM...Today through Saturday.

An upper level trough will sweep through the region today and
Friday. Rainfall/snowfall amounts look very light still, mainly
affecting the central mountains into the northeast highlands.
Expecting only a few hundredths of qpf and under an inch of snow
from this system. An isolated thunderstorm is possible this
afternoon and evening as well with some weak instability in place
across the region. Expect breezy southwesterly winds Thursday and
Friday but probably holding under wind advisory levels.

We will see a brief break Friday night before our next system
arrives Saturday. This is part of a much larger system that will
affect our weather into next week. Models are showing some weak
instability in place once again indicating that isolated
thunderstorms are possible. This does look like a somewhat wetter
system with around a tenth of qpf possible Saturday into Saturday
night.

13

.LONG TERM...Sunday through next Thursday. Next week will start out
cooler along with a decent chance of rain, mountain snow and even a
few thunderstorms. Snow will be possible down to around 6000ft (if
not a bit lower) at times, but any real accumulations on a daily
basis should be limited to at/above 7000ft. It will be breezy
through Tuesday especially across the Snake Plain and ridgetops. By
Tuesday afternoon, the forecast gets a little murky again. The
models, ensembles and cluster forecasts are pretty evenly split on
what will happen with the low moving toward the Plains. One camp
already has it heading into the Plains while the other holds it back
closer to our side of the Rockies. The Blend of Models looks
reasonable with the best chance of showers/storms closer to the
Wyoming border. A strong ridge rebuilds across our area by Wednesday
with a few lingering showers possible in the mountains especially
along the Wyoming border based on the Blend forecast. If the
strongest ridge scenario comes to fruition, we will be dry. The
Blend brings a better chance of precipitation Thursday, similar to
the GFS/weaker ridge idea. If the other camp (much stronger ridge)
wins out, we will again be dry. BOTH forecasts are certainly
plausible, so it`s difficult at this point to say which is the more
likely forecast. Keyes

&&

.AVIATION...A pattern change starts today with winds becoming South
and West today, as a low drops across region. Winds of 15-25kts will
impact BYI, PIH and IDA this afternoon and evening. Also, showers
with a few possible thunderstorms will develop later in the
afternoon and into this evening. At this point, it looks like
VCSH/VCTS will be possible at all of our TAF sites, especially DIJ,
PIH and IDA. Keyes

&&

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

$$