Weekend Warmth and Mountain Sprinkles — Southeast Idaho Adventure Outlook

October 30, 2025

This week’s weather story across southeast Idaho is straightforward and useful for planning outdoor adventures: a dry, slowly warming pattern through the weekend with only minor mountain sprinkles Sunday, followed by an increasing chance of wetter weather toward the end of next week. The NWS Pocatello Area Forecast Discussion points out a modest warming trend as low pressure systems skirt north of our region while high pressure hangs on to the south. Translate that for trail and river users: expect pleasantly mild days (mid 50s to mid 60s in many valley locations) and chilly, near-freezing nights — with mountain summits seeing scattered sprinkles or flurries primarily Sunday in the Sawtooths and around Island Park.

Short term through Friday night remains dry. High and mid-level clouds will drift in late today into tonight, but conditions will stay VFR and the ground will remain dry for day-hikes, road biking, and climbing approaches. The forecast notes a gentle warming Friday — highs roughly 5°F above today — so valley hikers and roadside rock climbers get an extra dose of comfort. Overnight lows will be a touch warmer than recent nights because the shallow inversions are weakening; still, expect frosty starts in the high country and places sheltered in basins.

The long term (Saturday through Wednesday) keeps the pattern of warm days and cool nights. Saturday looks mostly sunny with light ENE winds — a great day for long ridge runs, mountain bike laps on mid-elevation singletrack, and river float prep. Sunday a low sliding to our north tightens the pressure gradient a bit; winds will increase to breezy for exposed ridgelines and lake surfaces (WSW 8–18 mph is possible). The main precipitation signal stays weak: light showers, sprinkles, or a flurry confined to central mountains — mostly the Sawtooths — and the Island Park area. For alpine climbers and backcountry skiers, that means a sticky, mixed bag: a dusting at the highest elevations is possible but no significant accumulation is expected at lower alpine zones.

Model solutions diverge late next week. The Blend of Models is already nudging some precipitation into the picture by Wednesday night into the following weekend, and forecasters highlight that a pattern change bringing cooler temperatures and more moisture is likely by the end of next week. That’s an important planning flag: if you’ve got a multi-day alpine trip later in the week, monitor updates — rain at valley levels could switch to mountain snow at higher elevations as the trough amps up.

Practical takeaways for adventurers across the office area:

• Valley hiking, trail running, gravel or road cycling: excellent through Monday–Tuesday. Expect sunny to mostly sunny afternoons with highs in the 50s–60s, cool mornings around freezing, and comfortable winds. Pack a light insulating layer for pre-dawn starts.

• Mountain day-hikes, scrambling, and early-season backcountry: Saturday looks ideal; Sunday bring windproof layers and a waterproof shell for brief sprinkles or a light flurry, especially in the Sawtooths and Island Park. Trail surfaces will be dry in most places, but higher elevation routes will be colder and more variable.

• Fishing and river floats (Snake River, Henry’s Fork, local reservoirs): pleasant daytime temps and light winds Sat–Mon favor paddling and guided float trips. Be mindful of Sunday’s stronger breeze on open reservoirs and lakes. Water temps remain cool; hypothermia risk persists if a capsize occurs.

• Photography and sunrise/sunset outings: great windows this weekend. Mid and high clouds arrive late today and can enhance sunrise color, especially over the Snake River plain and the western Sawtooth ridgelines.

Hazards to respect: chilly overnight lows near or below freezing; gusty WSW winds Sunday across exposed ridges and plateaus that will make summit conditions feel cooler and can complicate pack stability and tent setups; light mountain showers/flurries Sunday in the central mountains; and increasing uncertainty for mid-to-late next week as a wetter, cooler pattern tries to move in.

Confidence in the near-term forecast is moderate to high: the warming trend and dry conditions through early next week are robust, while the later-week precipitation signal carries more model disagreement. Keep an eye on NWS updates if you have a trip planned after Wednesday.

In short: seize the weekend for valley and mid-elevation adventures — Saturday is the cleanest, Sunday stays usable but bring wind and wet weather protection for mountain travel — and begin watching forecasts closely for a pattern shift toward the end of next week that could favor wetter, cooler excursions and a return to mixed precipitation at elevation.