What does one pack when they know will be spending the next 3 or 4 days hanging out at the hospital?

I mentioned a few weeks ago that my husband's aunt was approved to donate a kidney and the surgery was coming up. Well, surgery is on Thursday, and I need to pack my bag to stay in a hotel while he's in the hospital. We live far enough from San Francisco to make commuting non-feasible, and he'll be in the hospital for about 4 days (the gods willing).

So what do I pack? And why is it always so freaking cold in the city? I live in a Bay Area "hot spot" (literally, we are always very warm), and I always freeze my ass off when I go into SF. Also, it's cold in the hospital. Should I look sorta warm and dressy, or cas and warm? Yoga pants? Leggings? Boots? Jeans? Gah!

I obsess over clothes to keep myself from obsessing over his surgery.