Why does it rain a lot in Seattle?
To the north of Washington state is Canada, to the south is Oregon, to the east is Idaho and to the west is Pacific Ocean. And in the middle is Cascade Mountain Range.
Since there is pacific ocean to the west of Washington, the water evaporates from it into the air and the condensation occurs where the tiny water droplets fall as rainfall.
The cascade mountain range sort of gathers all the moisture from pacific ocean. If you look at the weather for all the cities along this mountain range, including Victoria B.C., Vancouver B.C., Seattle, Portland, cities along the Canadian border like Bellingham, etc. they ALL get a boatload of rain and cloudy days, it’s not just Seattle.
One of the reasons I’ve heard is moist air comes in off the ocean, rises when it hits the mountains (mountains hold these moist air/water vapor), and the water vapor condenses in the colder air and falls to earth as rain.
Combination of being so close to the coast and having the mountains directly to the east. If you go to eastern Washington (Idaho) it is flat and desert like.
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