BOZEMAN – Big picture analysis of the western US has a weak High-pressure ridge over the pacific NW extending into Montana and a deep trough just off the southern California coast.
This is producing a milder WSW flow aloft and helping temperatures rise slightly above normal this week.
The California storm will dig into the SW US impacting travel across southern California, Nevada, Utah, and Arizona through Wednesday. This storm should weaken as it moves up into northern Colorado Thursday into Friday. This storm system should not have a direct impact on Montana’s weather except to bring continued mild temperatures through the end of the week.
The next weather maker is another trough developing off the pacific NW coast by Thursday and should begin to move inland by Friday reaching Montana by this weekend. This storm system will bring increasing clouds and a better chance for mountain snow showers this weekend and only a slight chance of showers for most valleys Saturday night into Sunday.
Behind this storm a cooler NW flow aloft will develop and will hold temperatures down mostly into the upper 20s to lower 30s next week. There will be several disturbances passing through Montana next week so plan on wintry travel impacts beginning Tuesday.