Area Forecast Discussion
Issued by NWS Missoula, MT
Issued by NWS Missoula, MT
078 FXUS65 KMSO 211832 AFDMSO Area Forecast Discussion National Weather Service Missoula MT 1232 PM MDT Sat Sep 21 2024 .DISCUSSION...Frost potential will be the primary impact tonight into Sunday morning across the lower valleys of western Montana and higher valleys of north-central Idaho. Otherwise, westerly flow will lead to tranquil conditions and seasonable daytime temperatures this weekend. A weak disturbance along the Canadian border will bring an increase in mid-level clouds on Sunday afternoon and evening. There is a chance of a few light showers, although showers will be mainly confined to northwest Montana. A mix of clouds and sunshine will continue Monday and Tuesday. Westerly breezes will pick up on Sunday and Monday afternoons as well with gusts of 15-25 mph. Temperatures will also warm to 10-15 degrees above normal (80s for many valleys) by Tuesday and Wednesday. The majority of ensemble clusters (about 70%) show a trough coming onto the Pacific Northwest coast late Wednesday into Thursday. This would open up the potential for showers and a few thunderstorms, and eventually cooler temperatures. There is also a 30-50% probability of wind gusts over 30 mph for western Montana valleys, 10-20% chance across north-central Idaho. The other scenario from about 30% of clusters, would support lower shower chances, less wind, and warmer temperatures as ridging tries to hold on. && .AVIATION...VFR conditions continue into Sunday under a westerly flow. A weak disturbance along the Canadian border will bring an increase in mid-level clouds on Sunday afternoon and evening. There is a chance of a few light showers, although showers will be mainly confined to northwest Montana. Westerly breezes will pick up on Sunday afternoon as well with gusts of 15-20 kts. && .MSO WATCHES/WARNINGS/ADVISORIES... MT...Frost Advisory from midnight tonight to 9 AM MDT Sunday for Flathead/Mission Valleys...Kootenai/Cabinet Region...Lower Clark Fork Region...Missoula/Bitterroot Valleys. ID...None. && $$