Fifty Plus (50+) - I drove today

For a few reasons. Primarily because I was picking up two [male/female] Ross 10 speed bikes. They are no prizes but I'll get my money out of them and pay for a couple bike items with the profit.
It was also supposed to rain. With temps over 70F and my fenders, DIY lighting I was ready. The rain missed us [darn drought] but they promise some rain over the next 48 hours.

On a completely different tack:
I just got a couple sleeveless polypro underlayer Ts to supplement my long sleeve jerseys. When the temps are in the 40's during the morning Ill try that combo. Using a long jersey and light jacket tends to cause too much heat and sweat buildup followed by chills [especially if I strip off the jacket].

back when I used to ride year round (same area as you) I found a wool jersey over a polypro undershirt was good down to pretty darn cold. there weren't a lot of days when I needed more than that on my upper body

since then I've acquired a wind vest with a nylon front and a mesh back. I think that the vest along w/ the jersey + polypro combo should be enough for any weather I'm ever gonna ride in again

Because of the extensive brush fires, the air quality was abysmal today. I do not plan to resume cycling or jogging until Thursday or Friday, depending on weather conditions.

When in the 40 degree range, I tend to wear an under-layer of polypro and a long sleeve jersey, but then carry a vest (very light weight and small enough to fit in a jersey pocket) for those long downhill stretches or if the wind picks up.

Riding in cooler weather requires layers and I have just got onto wearing a Base layer next to the skin. Never used to but it keeps me warm and dry. On those cooler mornings- I wear the base layer, then a S/S wicking cycle jersey and then the outer layer. If I can make that outer layer windproof- Then I will stay warm so I have cycling specific ones with full zips- and the material breathes. Problem is Sweat build up.I may be warm- but I feel damp. When I get damp- I cannot take the outer layer off as the wind will make me cold.

So I have a Variety of Outer jackets. The best by far is made of a material called Pertex. This is very lightweight and is in no way waterproof. It is however completely windproof- but breathes as though it were not there. Mind you- when it does get cold- It is useless unless I put on the L/S Jersey made of Roubaix material. Now that is warm.

For cold or even slightly cool weather cycling, I find a pair of full-fingered gloves to be indispensable.

The rain actually hit today but I missed most of the harder downpours. The performance clear rain jacket with vented sides and sleeves with a sleeveless jersey worked (60-70F). I also used rain pants over a pair of very light weight shorts and neoprene shoe covers. The polypro long fingered gloves got wet but stayed warm. If it was in the mid 40's I'd have worn sealskin gloves.
Last year I was too late switching over to my heaviest (and best quality) jacket. It has pit zips and breathes better. It moderates my temp better and moderates the dampness level. For those in between temps - 45 - 55F I'm thinking long sleeve jersey with sleeveless underlayer or short sleeve jersey with very light windbreaker.