A ridge of high pressure and the passage of a cold front brought copious amounts of sun to Montana and Wyoming on Saturday, but cooler than average highs. We can expect a clear night as we head into the first morning of fall on Sunday. The clear, dry air and light wind will lead to cooler lows for everyone in the 30s and lower 40s.Sunday will begin clear and cool, and summer will turn to fall at 6:44 MDT. Much of the day will be clear, but we'll have increasing clouds late in the day ahead of another fast-moving disturbance on Monday. At this time it appears we won't have any good chances for rain from it, but we'll cool down with slightly stronger breezes by Monday afternoon.High pressure will rebound over the region on Tuesday, and it will stay in control of our weather pattern for most of next week. That will lead to a rapid warming trend to above average levels through next Saturday, but our highs will likely peak on Wednesday. A small disturbance will pass north of us, but will only bring breezes and a minor cooling trend.