The seasons are:
Summer: very nice, usually sunny mid-70's to mid-80's with a few days a summer getting into the 90's
Spring: rain, but the closer to summer you get the nicer it is. The rain usually isn't hard but it tends to be constant.
Winter: Usually a couple days of snow or ice a winter. Usually cold, 40's. There is rain too, but there can be nice sunny (but still cold days). There also can be pretty nasty east winds blowing out of the Gorge.
Fall: early it's still sunny and nice, as October goes on it gets colder and colder at night. When the rains starts varies each year, but usually late Oct. or early Nov.
Yes, I know my location says Long Beach, but I spent 27 of my 29 years of life just 10 miles east of Vancouver.