textproduct: Pocatello

KEY MESSAGES

- Above average temperatures will continue, even a cooldown coming our way

- Wet and windy conditions start tomorrow, but pick up especially mid to late week

- Potential for a significant mountain snow event the end of the work week

SHORT TERM /THROUGH MONDAY NIGHT/

Issued at 1224 PM MST Sun Dec 14 2025

High pressure slips off to the east tonight, opening the door for a longer duration period of wet and windy conditions. The first surge of moisture arrives tomorrow afternoon for the central mountains, but don't expect much if anything outside of the Sawtooths and surrounding ranges. That band should gradually dissipate as it shifts across the Snake Plain and east of I-15. A better surge of moisture arrives tomorrow night, with higher amounts across the central mountains (especially the Sawtooths/surrounding ranges) and the eastern highlands. Some lighter rain and high elevation snow is possible across the Magic Valley/South Hills, extending along the benches back toward the Big Holes. Snow levels actually rise tomorrow night as this will be another surge of Pacific moisture, with the typical increase in temperatures and snow levels. They will rise above 8000ft except for east of I-15 where they remain 5000-6500ft. By sunrise Tuesday, we could see a quick couple of inches of wet snow for the Sawtooths.Temperatures even with the arrival of more clouds and precipitation should remain 10-20 degrees above average, dependent on location. Wind picks up mainly across the central mountains and along the benches as downslope increases.

LONG TERM /TUESDAY THROUGH SUNDAY/

Issued at 1224 PM MST Sun Dec 14 2025

The pattern throughout the extended remains very similar to previous forecasts. Moist system encroaches into East Idaho Tuesday into Wednesday. Temperatures remain mild with this event, despite cold front spilling into the region Wednesday. Snow levels Tuesday range from 6500 ft in the Island Park region to near 8000 ft across the South Hills/Albion Mountains. Precipitation Tuesday is largely focused across the Central Mountains and Island Park/Big Holes regions. Precipitation becomes more widespread Tuesday night into Wednesday across the region, reaching many lower elevations. Even though the cold front will have the potential to bring snow levels close to valley floors late in the day especially across the north half of the forecast area, the bulk of the precipitation should be shifting east by then. Thus little, if any, accumulation is expected at lower elevations. Total snow accumulations for this event range should be highest across the central mountains. NBM means carry up to 2" of accumulation at lower elevations here, rapidly increasing up to 6-12" above 7000 ft. 90th percentile amounts rise to 2-4" for the Stanley Basin and up to 18" across the majority of the Sawtooth Rec Area. Winds will be strongest Wednesday associated with the frontal passage, and NBM means are strong enough to support wind headlines for the day.

Following a brief break Wednesday night into early Thursday, the next in a series of systems rolls into East Idaho late Thursday. This system looks to be more potent, with a more continuous deeper stream of moisture, lasting into early Saturday. Temperatures at lower elevations remain mild for rain or a rain/snow mix during the day, and very light snow or rain/snow mix at night. At higher elevations, this could be a more significant snowfall producer for the mountains. Ensemble clusters are in good agreement this far out, so the confidence is moderately high for a significant event potential, but it is still quite early to be thinking about details. Stay tuned through the week.

AVIATION /06Z TAFS THROUGH 06Z TUESDAY/

Issued at 1028 PM MST Sun Dec 14 2025

Very light winds and just a few high-level clouds remain on tap for the next 24 hours or so at all terminals, with the usual diurnal wind cycle at KSUN. We start to see hints of some modestly more organized wind flow (still 7kts or less) and increasing clouds Monday afternoon ahead of our next weak system. CAMs are looking a bit messy by mid-afternoon or evening, but confidence still isn't there to add any precip impacts aside from VCSH for KSUN Monday evening/overnight. Overall moisture looks quite limited with this system, with the better chance of impacts to aviation (including strong winds) holding off until Wednesday.

PIH WATCHES/WARNINGS/ADVISORIES

None.