Year-round humidity in SF? (San Diego, Richmond: apartment, purchasing, live)

[ratatouille]

So I just moved to SF and was debating purchasing a dehumidifier. It's been 57-72% inside my apartment the past 2 weeks and was wondering if I should expect this to go up or down come fall and winter. I've already looked at the weather trends for humidity on the city-data page for SF but it conflicts with other weather sites I looked at.. Also, I'm in Outer Richmond by 40th Ave.

[mayorhaggar]

The air here is pretty dry, even when it's foggy or raining out it doesn't feel humid and swampy like the Deep South or whatever. It will get drier when it gets colder from around October to December, then it starts raining until around March or April though it's so cold that the rain doesn't really make it feel humid. It's up to you and how comfortable you feel.

[ragnarkar]

Dewpoints are generally 50 - 65 here (but 55 to 60 the majority of the time.) Not exactly humid but still within my comfort zone.

[clongirl]

Originally Posted by ratatouille

So I just moved to SF and was debating purchasing a dehumidifier. It's been 57-72% inside my apartment the past 2 weeks and was wondering if I should expect this to go up or down come fall and winter. I've already looked at the weather trends for humidity on the city-data page for SF but it conflicts with other weather sites I looked at.. Also, I'm in Outer Richmond by 40th Ave.

The damp fog and wetness will make the mold/mildew in your apartment wreak havoc on your clothes and furniture. I used to get this nasty, smelly black mildew in my closets and in the carpeting in just about every apartment I've ever lived in. I think a dehumidifier would have helped that.

[ratatouille]

I think I may just get one regardless. I agree that it never *feels* humid because it's cold and humid, not hot and humid, but I have some collectible items that are humidity-sensitive and I also use a portable washing machine inside my apartment and then hang dry the clothes inside. This usually ups the humidity quite a bit for several hours.

[rah]

SF isn't very humid aside from when it's foggy. I guess it's a bit humid overall compared to Phoenix or something, but not compared to anywhere in the south/east/midwest. SF has a Mediterranean climate, which means that aside from winter (and fog of course), it's a pretty dry place.

[andyadhi01]

Originally Posted by rah

SF isn't very humid aside from when it's foggy. I guess it's a bit humid overall compared to Phoenix or something, but not compared to anywhere in the south/east/midwest. SF has a Mediterranean climate, which means that aside from winter (and fog of course), it's a pretty dry place.

That's a pretty vague statement because its either foggy or rainy 80% of time of the year....

[mayorhaggar]

Plus in winter it gets dry inside when you have the heater on all day, sometimes I need a humidifier because my eyes get so dry.

[Gentoo]

SF is dry as far as humidity is concerned. The cold water nearby is a big factor in that. Compare it with San Diego which can see dewpoints into the mid 60's some years and that is damn uncomfortable. Most of the year SF's dewpoints are in the 40's and during summer usually the mid 50's which is still comfortable.

[tstieber]

Originally Posted by andyadhi01

That's a pretty vague statement because its either foggy or rainy 80% of time of the year....

Foggy, yes -- I'd say 95% of the time in the Richmond, where the OP lives. Rainy, less than 20% of the time (on average over man years, the last couple winters and springs being glaring exceptions, but they average out with drought years).

All in all, SF humidity is relatively low, but I know people who have mildew too. I find that they don't ventilate and open their windows, so much of the indoor humidity comes from showering.