As has been said, it's best to look around and see what you have. For a windbreaker, I use an old hockey jacket that I hadn't worn much, it's usually good to about freezing, depending on the wind. It's water repellant, too. I have a Gore- Tex jacket that I have found to be too warm for temps between 20 & 30 F, so I just bought a breathable/waterproof cycling jacket with pit zips and ventilation that should work. It's a Louis Garneau Spotlite. So far this fall, all I've worn underneath the jackets is a short sleeve cycling jersey and a long sleeve tee shirt, been toasty warm.