088 FXUS65 KMSO 101020 AFDMSO Area Forecast Discussion National Weather Service Missoula MT 420 AM MDT Wed Oct 10 2018 .DISCUSSION... High-elevation snow showers will be slow to dissipate across the Northern Rockies through the remainder of this morning, creating slick conditions and low visibility on mountain pass roadways (including MacDonald Pass, Lost Trail Pass, Marias Pass, and others). Most of the snow activity will be confined to near the Continental Divide. By this afternoon, a mid-level cloud deck will remain and keep high temperatures below the seasonal average. The Northern Rockies appear to be locked in a persistent large scale northerly flow pattern indefinitely. Another Continental Divide mountain pass light snow event is anticipated again Friday night/Saturday...and yet again Monday/Tuesday next week. The impacts from these two systems will be similar to the current one, with some easterly wind gusts through mountain gaps (e.g., Badrock Canyon near Columbia Falls) and slick roads, low visibility over mountain passes (e.g., MacDonald Pass). Those heading into the backcountry will find inhospitable wintry conditions at times. Operational models continue to ballyhoo warm, dry high pressure over the Northern Rockies late next week, however the continual delay of this high pressure with each model iteration is nothing short of irritating for both forecaster and forecast consumer. Despite models depicting a "change" in the extended periods, there is little in the global weather pattern suggesting that we're finally going to experience warm, dry conditions for north central Idaho and western Montana in the next 10 days. Bottom line: the trend of wetter, colder continues for the Northern Rockies for the next week and beyond. && .AVIATION... Low clouds and high-elevation snow showers will remain over the Northern Rockies air space through 10/1800Z. KBTM will the most impacted terminal with both low ceilings and obscured terrain. Terrain obscurations will be concentrated near the Continental Divide and across southwest Montana, Lemhi County Idaho (including near KSMN). Even the valley stratus that is elevated above high terrain will be slow to dissipate throughout the next 24 hours. Winds today will be relatively light compared to Tuesday. && .MSO WATCHES/WARNINGS/ADVISORIES... MT...Winter Weather Advisory until 9 AM MDT this morning ABOVE 5000 FEET for the Bitterroot/Sapphire Mountains... Butte/Blackfoot Region. Winter Weather Advisory until 9 AM MDT this morning West Glacier Region. ID...Winter Weather Advisory until 9 AM MDT this morning ABOVE 5500 FEET for the Eastern Lemhi County...Western Lemhi County. && $$