http://www.scarsports.com/ARGRmarathon.html
This is a first year marathon in Sacramento on the American River Parkway. It is a great trail. I expect this to be a very fast course. It has a net elevation loss of 450 feet over the 26 miles. There are a couple of small-ish hills, but from the profile nothing appears to be more than 50' elevation gain at a time.
Weather should be good, but there is always a chance of rain in Northern California in November. Plus, its one of the few Saturday races around.