How does the Pacific North West average such low dew points when it’s known for its precipitation?

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How does the Pacific North West average such low dew points when it’s known for its precipitation?

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Because the air there is quite cool. The air in the PNW doesn’t actually have that much water in it, but the cool temperatures allow that water to easily condense out and fall as the region’s characteristic light drizzles. It’s also assisted by the mountains, which cause air to rise and cool and tend to squeeze much of the rainfall out of each air parcel (which is why the inland portions of Washington and Oregon are arid grassland).

In terms of actual total rainfall. the PNW outside of the mountains gets a decent but not insane amount. Seattle gets 37 inches of rain a year. Compare Miami, Florida (67 inches, despite having fewer rainy days than Seattle on average), Atlanta, Georgia (50 inches), or Washington, D.C. (42). It rains a *lot*, but not very heavily. The parts where there actually is a ton of total rainfall (like the Hoh Rainforest, which averages nearly 200 inches a year) are mostly in the mountains.

ELI5? Dew point is mainly affected by humidity and temperature and it’s rarely very humid in the PNW

I live in the PNW. West of the Cascades. It’s humid I do live off the Colombian river , I’d have to look at my records. I would wager an AVG. Of 70-80% . I’ve seen it as low as mid 30% and as high as mid 90%.
I don’t have any fact’s why it’s so humid. Calling our own pnw guy Bill Nie.
My idea is we have a lot of water everywhere river’s, lakes and in the soil. It’s everywhere just like in the Ocean or a island. That being said I know the East Cascades is a lot dryer in my area My Adams and My. Hood, To the North Snowquilame pass, to the Grants pass.