National Weather Service Weather Forecast Office

• Home
• Site Map
• News
• Organization
• Search for: NWS All NOAA 

000
FXUS65 KPIH 230847
AFDPIH

Area Forecast Discussion
National Weather Service Pocatello ID
247 AM MDT Tue Apr 23 2024

.SHORT TERM...Today through Wednesday Night.
It`s a fairly quiet start to the morning, though moisture is just to
our south as evidenced by water vapor imagery and radar returns in
central Nevada and Utah. It`s this band of moisture that will slowly
lift northward today into parts of the Southern Hills and
southeastern Highlands. The uncertainty with this is exactly how far
north it will make it this afternoon with the NAM wanting to bring
showers as far north as Burley and almost to Pocatello while most of
the other models don`t come that far north. Most of this activity
looks to be showery, but the potential for thunder is very low
- less than 10 percent. We also start to warm up again today with
highs in the valleys reaching the mid to upper 60s. The warm up
continues on Wednesday with highs about 5 degrees warmer, pushing
many of us into the low 70s. As troughing off of the west coast
begins to move inland on Wednesday, another round of showers will
lift northward into our area again, becoming more widespread and
including some afternoon thunderstorms. The best chance for
thunderstorms on Wednesday, around a 40 to 60 percent chance, will
exist along and south of I-84 with a 20 to 40 percent chance
south of Idaho Falls. This is just the start of our return to a
more active pattern, but temperatures will also fall after
Wednesday.
AMM

.LONG TERM...Thursday through Tuesday.
Models remain consistent in bringing a deep trough into the
region for late week. Best rain chances remain over the eastern
highlands on Thursday with some downslope effects likely in play
from the central mountains into the Snake Plain. Looking at likely
to almost certain chances for precipitation Friday into Saturday
as the low moves overhead. Snow levels for this event are expected
to be around 7000 feet which should translate into limited
impacts. QPF amounts range from 0.25 inches of less in the Snake
Plain and Magic Valley to 0.50 to 1.00 inches across the eastern
highlands.

Forecast becomes much more uncertain starting Sunday as this system
pulls away from the region. Models show another low pressure system
entering the Pacific Northwest, but are not handling its progression
inland well at all. Lots of inconsistency from one model solution to
another in terms of speed, track and intensity. So we have a low
confidence forecast from Sunday onwards with at least some form of
low rain chances in the forecast.
13


&&

.AVIATION...Winds should be much lighter today across the region.
Typical downvalley switching to upvalley winds expected at KSUN for
the afternoon. Showers are expected in the south hills this
afternoon, which could encroach upon BYI although most models keep
activity south. Otherwise ceilings expected to remain vfr today.
13


&&

.HYDROLOGY...No major changes in the hydro forecasts at this
time. Water levels on the Portneuf river continue to run high,
just below moderate flood stage for the Portneuf river in
Pocatello. The river forecast for the Portneuf river in Pocatello
shows the river running above flood stage for the foreseeable
future and likely climbing back to moderate flood stage by
Tuesday. At Topaz on the Portneuf, current levels remain very near
minor flood and are forecast to rise above minor flood stage by
late Tuesday into Wednesday. Thus, have upgraded the flood
advisory on the Portneuf at Topaz to a flood warning. Water levels
are forecast to slowly rise toward the end of the week with
warming temperatures through Wednesday and the return of
precipitation chances in the second half of the week into the
weekend.
Wyatt


&&

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

$$