Boise, ID – Unseasonably warm temperatures are expected to continue through the end of the week across southwestern Idaho and parts of southeastern Oregon, with daytime highs climbing well into the upper 50s before a gradual cooldown arrives this weekend, according to the National Weather Service Boise.
Cities including Boise, Caldwell, Meridian, and Ontario will see highs ranging from 56–59°F on Thursday and Friday, while McCall and other mountain areas will stay cooler, topping out in the mid-40s. Morning lows across the region will generally remain above freezing, keeping travel conditions mild for mid-December.
A weak system may brush the central Idaho mountains Thursday, bringing light precipitation chances of 10–20% to areas such as McCall and Idaho City, but most locations will stay dry through early next week.
“Warmer daytime temperatures in the upper 50s are expected for most areas tomorrow and Friday,” the National Weather Service Boise said in a Wednesday update. “The weekend will see a slight cooldown into the lower 50s and upper 40s with drier conditions.”
Temperatures will dip slightly beginning Saturday, with highs closer to 48–52°F in the valleys and 40s in the mountains. Overnight lows will fall back into the upper 20s to mid-30s by early next week as high pressure weakens.
Despite the cooling trend, no significant storms or snowfall are forecast through Tuesday, making for relatively calm mid-December weather across southwestern Idaho and eastern Oregon.
Residents are encouraged to enjoy the mild stretch while it lasts—colder air and more active weather patterns are expected to return later in December.
