Today, a ridge will move farther inland and its center will plant itself directly over the Pacific Northwest.
This ridge will begin moving east as the week progresses, and due to this eastward movement, Montana will see a significant warming trend throughout the week.
Wednesday should be the warmest day we've had in Montana so far this year. Areas of Montana will see temperatures in the sixties, along with plenty of sunshine. By Wednesday afternoon it isn't out of the realm of possibility for Helena, Great Falls, or both to possibly top 70º.
Late Wednesday night into Thursday will be the first chance for precipitation during our work week. As the ridge moves east, the upper-level flow will flatten behind it. This will allow a quick-moving shortwave trough to develop. This shortwave trough will mainly bring rain chances along the high line. Mild sustained wind with strong gusts are likely this week as atmospheric high pressure settles over the state.
Some model data is suggesting some small chances for showers over the weekend, but they aren't all in agreement yet so don't count on it. It appears that after the chances of light precipitation this week and Monday Montana will head into a decently-prolonged period of warmer and drier weather which will be further intensified by a number of ridges that will settle over the West Coast of the United States.