San fran is okay, the indoors have heatings, not like Northern
Thailand.
Here's some ideas so as not to make your luggage too heavy. I hope
you are female though.
a) Take along a lightweight cashmere/pashimina/silk shawl in your
hand luggage. It can serve as a scraf for your neck, lightweight
head covering ala our muslim sister & a big enough shawl for
when you are dinning indoors at a heated location. In the hand
luggage; you can also pull it out, fold into a small pillow on the
plane.
Get those plain reversible colour ones. I got mine at Bugis Juction
Stall, 2 for $15.
b) Socks, get those sports socks a size bigger, they are slightly
padded at the soles and are of a tighter weave so you can be kept
warm when you sleep. Even under covers in bed, your bare feet most
likely will feel the cold then the rest of your body in
pyjamas.
c) Gloves, those cheapo woolen tight knitted ones works best.
Stuffed them into your jacket pocket so its easier to locate them
when you put on your jacket.
d) And if possible, a toque, balaclava or at least tight on your
head jockey cap cos heat escapes easier thru the head. (You can use
the cashmere/pashmina/silk mix scraf too as a temporary measure but
I am sure you might want something you wont have to adjust every
time.
e) those long sleeve long pants inner winter wear thingy, they look
horrible, hard to take off and may puff you up like a michelin man,
but they save my soul when I was in northern Thailand and I was
regretting not bringing it on USA tour where we camped outdoors in
the cold. Just take one set just in case in your luggage lah. And
wear it when you are going to be outdoors near the sea area. (Just
in case you want to tour alcatraz or fisherman market or take the
cable car at night. they call the trains at San Fran Hyde Park
cable car cos it operate by cables.) The innerwear dont cost much
either.
f) A waterproof padded jacket with hood make sure that is at least
a size bigger then what you tried on in Singapore.
I got one from that Stella & keith ...kinda hip hop apparel
chain shop for $29.90 and it looks okay.
g) Bring rubber slippers, not the thongs kind where you a strap
goes in between your big toe & 2nd toe. Those a bit like ah pek
kinda slippers where its a broad strap that goes over from both
side of the slipper.
I find them useful for wearing into the shower, toliet at the house
or hotel room , especially in your socks. And it protects you from
the chilly shower floor and those hidden floor germs that might
give your feet ringsworms and so on.