BOISE, Idaho – The air feels sharp and still this morning across the Treasure Valley, with faint fog clinging to low fields near the river. Temperatures hover in the upper 30s at sunrise, but skies are clear—an early sign of a comfortable, golden stretch leading into Halloween. For now, the calm dominates after last week’s chill, and sunshine will steadily rebuild through the day.
According to the National Weather Service in Boise, a strong ridge of high pressure will strengthen across southwest Idaho through Friday, keeping skies bright and temperatures seasonal. Highs will reach the mid-50s today, climbing into the upper 50s Thursday and near 57° Friday. Early mornings will remain cold, with lows dipping to near freezing, so residents should protect tender plants and plan for frosty windshields on early commutes along I-84 and Highway 55.
Friday’s Halloween weather looks ideal for trick-or-treaters across Ada and Canyon Counties. Expect sunny skies, dry roads, and light evening winds. Temperatures should hover near 55° in the afternoon, cooling to the mid-40s by dusk—a crisp but pleasant setup for costumes and outdoor events.
Saturday will stay dry and warmer, with highs in the mid-60s before a weak system passes late in the evening, possibly bringing a sprinkle north of Boise. By Sunday, clouds clear again, setting up another bright, calm start to November.
To be fair, this stretch is about as good as it gets for late October—sunshine, light winds, and cool nights perfect for fall activities. After all, clocks fall back at 2 a.m. Sunday, signaling earlier sunsets and a hint of that inevitable chilly November pattern ahead.
Five-Day Forecast for Boise, ID:
Wed: 56/32 – Mostly cloudy early; clearing and calm.
Thu: 56/34 – Mostly sunny; frosty start, light wind.
Fri: 57/42 – Mostly sunny; perfect trick-or-treat evening near 45°.
Sat: 66/46 – Mostly sunny; slight shower chance late.
Sun: 61/37 – Partly sunny; breezy and mild.
