The Bay Area Weather is wonderfully weird!

I shall continue with my "California tutorial" with a discussion of the Bay Area Weather....

When I moved to the Bay Area back a decade or so, I was shocked by the weather....  It was nearly perfect, always!  I mean winter, summer, spring, fall, the weather was about what you would get if you designed a giant self contained climate controlled biosphere hurtling towards Mars or something.  I would just walk outside without a jacket or shorts or whatever and marvel at how great things were, then I would call up my parents back in Connecticut and just laugh and laugh, until they would be all "hey can we talk about something else now...." and I would be like "OK", but I wouldn't really mean it and then I would wait a bit and then just yell something like "gotta open my umbrella ....NOT!"

My friend Mark has moved to San Francisco, so I know what he is thinking at this point....  "Whaaaaa????".   I am sure that his experiences are not the same.  Bare with me, I will explain further.

But I am a curious guy, and SF isn't really at that different of a latitude than DC, which has pretty hot summers and cold winters.  How could things be so different?  The seemingly immutable rules of weather that I had grown up with dictated that there were seasons that were extremely warm or cold, and you *could* move to some southern place to avoid snow but you would pay for it with furnace hot summers and giant crickets and people speaking with funny accents.  Not only do people not have accents in the bay area, but we don't have so much as a thunderstorm, and snow is a once in a decade event.

Here is a reference describing some of the reasons.  It is all a really bizarrely grand conspiracy with many parts that lead to a giant natural climate controlled system....

• cold arctic currents flow off the west coast
• warm deserts sit to the east
• warm air rises (duh!)

As the summer hits, the desert air heats, raising and sucking cold air from the ocean over the bay.  Effectively this acts as a giant air conditioner that cools the whole Bay Area.

Furthermore, the pressure gradient causes a quick condensation of the moist ocean air, leaving a layer of fog near the ocean (ie- San Francisco), and no humidity elsewhere.  The fog adds to the air conditioning effect that is already at its maximum in the west and makes these places miserably cold all year long.  

As you cross the Bay Eastward, the fog ends, and the air starts to warm up.  Eventually you will hit the deserts, but somewhere in the middle (precisely in the midpoint of the Popeye's Chicken on San Pablo Ave, I believe) the weather is perfect all year long.  This is about where I first lived in the Bay Area.

Now you can understand what people mean when they say "microclimates".  The whole idea seemed crazy to me at first, that the Bay Area has these city sized zones of regular weather patterns, and that you could actually drive to them and experience a different climate.  But it is true.  I used to stand in the Berkeley Hills on a beautiful spring day (in, say, December) observing a cold looking San Francisco completely covered by fog, and I would slightly raise an eyebrow, tilt my head and utter "fascinating" in a Vulcan like voice.

Some days the fog does roll right up to our house in the hills to the east, and when I wake up it fills up the bay like a lake, with us on the shore of a beach on a beautiful day.  I have to remember to bring my coat on those days, for once I drive minutes downward, I cross the magical fog line and suddenly find myself in a cold, dreary place.  I take comfort in knowing that beautiful weather is only a drive away.

Soon after I arrived in CA, I visited Sacramento.  It is a kind of boring town with a cool little "wild west" historical district in the middle.  What really stuck out to me though, was that after about an hour or so of driving, I suddenly realized how hot things were becoming, and looked at the temperature....  It was about 100 degrees!  At first I thought a heat wave was hitting, but when I headed back to the bay, everything was back to about 70 degrees, and no one was complaining about it having been a particularly warm day.

A few years back, a rare heat wave hit, and the east bay was extremely hot for a few days (one of the only times I remember this happening over the last decade).  We were miserable, but the solution was simple....  We drove to San Francisco which itself was experiencing a heat wave.... in the 70s!

Every town in the area has its own climate, you will become familiar with them as you travel around.

You will often hear it said that the Bay Area doesn't have seasons....  Lies!  We do too!  They are just places instead of times.  Get in a car, you can drive to any of them:

• Summer- Anywhere about a half hour east of the Bay, including the Pleasanton/Danville area, available by Bart.
• Spring/Fall- Berkeley
• Winter- Tohoe, Baby!

Yes, you can experience snow and all of its companion preppy like activities by driving out out to the hills.  Last year, Z and I got trapped in a snowstorm somewhere pine'y and eastish in like April or May.

OK, I lied a bit....  The Bay does have a slightly bad time of year, the rainy season, which hits around Jan-Feb.  When I first heard of the rainy season, I imagined monsoons, but it isn't like that.  In reality, during those times of the year, the outdoors are often in a constant state of "almost rain".  Occasional drops will hit, and you might get a minute of drizzle, then it will go back to its normal dreary state.  When the clouds clear up, it *can* go back to t-shirt weather even in January (although typical January temps are in the high 40s, and it rarely goes into the 30s during the day....  It is more likely that it will go up to the high 50s than that).  If this becomes too burdensome, I have two words for you....  Tiujuana, baby!

You never see thunderstorms, you never see snow (never = once per 5 year period, and everyone says "did you see the snow?" for the next year).

From what I hear, LA is kind of like this also (with its good and bad microclimates), but on average warmer.  Some people find the Bay average a bit too cold, some people find the LA average a bit too hot.

There you, go, I have finished my whole post about weather in the Bay Area without once mentioning that cliched fake Mark Twain quote about SF (you can google it).