As I’m getting into running 3 days a week, I’ve been doing a lot of experimenting with what to wear. Burbank mornings are in the high 40s; here in Oakland it’s been down closer to 40. I think I got it right in Burbank last week, with a sleeveless compression top with built-in bra, and a long-sleeved shirt (wicking, of course) over the top. I’m chilly when I first start but comfortable-to-warm towards the end. Last couple weeks in Oakland I’d tried a fleece hat, and that proved to be too much, so today I pulled out my fleece head/earband and that seemed to be just right. I wear two full long-sleeve layers here, though both are fairly lightweight. I think I had just about the right balance this morning. There may be colder mornings, but I don’t recall it getting a lot chillier than this down here.
Edited 11/27 to add that I found a pair of running “tights” that I actually like … they’re a good weight for this climate and not too, and they have pockets - nice to have a place to stash a key. I found ‘em at Sports Authority and was hoping to find them online for a better price, but they don’t seem to be sold anywhere else - must be a Sports Authority house brand or something. The brand is “Aspire” and they’re called the Quest Run Pants.