Boise, ID – The Treasure Valley wakes under a dull gray ceiling this morning, the air heavy and still before another round of December rain settles in. Roads are damp, the hills are misted, and a calm start will soon give way to a wet stretch through early week.
Meteorologists with the National Weather Service in Boise are tracking a series of Pacific systems sliding inland, bringing intermittent rain from Sunday through Tuesday night. After a mild and mostly dry Saturday, light showers return Sunday afternoon, followed by steadier rainfall Sunday night into Monday morning.
The rain may briefly mix with patchy fog in the lower valley, reducing visibility on I-84 and Highway 55. Highs will remain above freezing — upper 40s to mid-50s — but persistent dampness and cooling nighttime temps could still create slick patches on untreated roads in higher terrain north and east of Boise.
By Tuesday, showers increase in coverage with a 70% chance of rain, possibly tapering to scattered drizzle by Wednesday. Beyond that, a weak cold front could pull temperatures back toward seasonal norms, though long-range guidance hints at a return to active Pacific moisture between Dec. 11–17, potentially bringing colder rain or early snow to Idaho’s mountains.
Five-Day Outlook (Boise, ID)
Sunday: Chance of rain, high 48°F, low 39°F.
Monday: Rain likely, high 53°F, low 44°F.
Tuesday: Rain likely, high 55°F, low 47°F.
Wednesday: Showers continue, high 54°F, low 45°F.
Thursday: Mostly dry, high 57°F, low 43°F.
