I 2nd the recommendation on arm and leg warmers. If I need additional, my next step is a vest with a double-ended zipper...that way I can unzip it partially from the bottom without creating a parachute. Also a buff/neck gaiter is handy too.

This time of the year, the local temp ranges from comfortable to just plain hot, so clothing is pretty easy to figure out. Once into late fall, is when it gets tricky. My average late season loop, not only will I deal with freezing temps in the morning, but I also have to couple that with about 1 to 1.5 hours of mostly descending at the beginning of the ride. Then I'll spend the last leg of the ride, climbing with temps about 20 degrees warmer. I've finally just settled with the arm/leg warmers and vest...I know I'm going to be really cold for the first hour of the ride, but I'll be comfortable the next 3 hours and not have to lug around my winter gear.