Yes, come out here, like all the guys at work tell me, why sign up for a century, do your own. There are lots of great rides around here and stores the whole way you can use for support. Taxis make great SAG support, do it.
San Francisco Randonneurs organize a Populaire (115K) from San Francisco to Point Reyes Station on Jan 11 with a picnic lunch at the end, also a harder 200K ride to Point Reyes Lighthouse on Jan 25. These are rain or shine, and it will often be cold or rainy at some point in the ride.