Boise, ID — The Treasure Valley wakes to calm skies and a crisp chill, but clouds are already thickening across southern Idaho as a Pacific system slides inland. By midday, gray skies will dominate, and by afternoon, steady rain showers will begin to fill in across the Boise metro area. The air feels damp and raw, with highs only around 43°F, and winds light but persistent from the southeast.
Meteorologists expect rain to intensify by late today and continue through Friday morning, with up to ½ inch of accumulation possible in valley areas. Roads will turn slick, and reduced visibility could slow the evening commute on I-84, especially between Nampa and Mountain Home. Temperatures will remain too warm for snow in the city, but mountain zones north of 5,000 feet could briefly mix with flakes.
Friday stays gray and soggy with highs near 46°F, but by Saturday, the system begins to weaken — still leaving scattered showers and highs near 50°F. Another weak disturbance is expected early next week, keeping Boise locked in a mild, wet December pattern.
Five-Day Outlook (Treasure Valley):
- Friday: Rain tapering late, high 46°F, low 39°F.
- Saturday: 30% rain chance, high 50°F, low 33°F.
- Sunday: Mostly cloudy, high 49°F, low 38°F.
- Monday: 40% rain chance, high 52°F, low 40°F.
- Tuesday: 40% rain chance, high 59°F.
