Wonderful--I've lived in Silicon Valley for the last 30 years now, ten in San Jose. No, wait, twelve. Time flies.
We are fortunate here in having a diverse ethnic community and moderate weather--most of the time. It is pretty informal overall, but some areas are more into dressing up than others.
As I've gotten older and have thyroid issues I feel the cold more. Warm sweaters are definitely useful, as are winter jackets. It all depends on your personal refrigeration-heating system and where you live. We must have dozens of microclimates here. You won't need a winter coat or a heavy jacket unless you need it for travel. My son lives in Chicago--we often go there for Christmas.
We get several episodes of 100°+ weather from May to even October. It usually only lasts a few days. The coldest time of year is from late December to early February. Last average frost date is January 25 where we live. Some years it doesn't get below freezing, others it gets into the 20s. Again, it depends on the microclimate where you live.
DH and I take continuing studies classes at night at Stanford and we call the place foggy bottom. Puffy coat or jacket, gloves and hats are needed to walk from parking to classrooms.
Fuzzy jammies--well I have a couple of pair of flannel pjs I occasionally wear in winter. The rest of the year they are stuffed into a cupboard.
The first 5-6 years we lived here I didn't have a winter coat at all. We moved here from Southern California. I wear wool and leather jackets most of the year.
I imagine it will be quite a change for you. San Jose is going through some traumas due to the recession. We love it here because of the variety of cultures and people.
Any specific questions there are several of us who could answer.
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