On Saturday, mountain areas started off with frigid temperatures as McCall reached -3°F and Stanley dropped to -17°F. The Treasure Valley woke up to temperatures in the mid to upper 20s. A warm front is approaching, bringing cloud cover from southwest to northeast and kicking up a strong southeast breeze with gusts up to 40mph possible for the evening.
Expect widespread precipitation with the warm front overnight into Sunday morning. The storm will pass quickly, with most of the precipitation falling overnight. Temperatures should be cold enough for some snow in the Treasure Valley before transitioning to rain, with expected snowfall of a dusting to 2 inches, favoring the Boise foothills.
Watch for slick roads on Sunday morning in the mountains as more substantial snowfall amounts are expected, with 3-6 inches in the mountains and 1-3 inches in mountain valley communities. The National Weather Service in Pocatello issued a Winter Weather Advisory for the Sun Valley Region, Stanley Basin, and Sawtooths.
It will remain breezy on Sunday, but sunshine returns for the afternoon and evening. Valley spots climb to around 50°, so any snowfall will melt fairly quickly. The next round of moisture impacts the area Sunday night through Presidents Day. However, snow levels will be a bit higher with rain expected for the Treasure Valley. Light snow amounts of around 1-4" for the mountains.
Southwest flow will allow us to tap into some moisture from an atmospheric river impacting California. While we are not expecting a major storm next week, it will continue to be unsettled through Thursday morning and seasonably mild temperatures continue.
Beyond that, model guidance indicates that an upper level ridge will strengthen over the region from Thursday to Sunday, providing quiet and mild weather just in time for the McCall Winter Carnival.
