Feels like 12 degrees

Temp: 20, but feels like 12, mostly sunny
Wind: Yes! Between 10 & 20 mph, with gusts up to 30
Precip./Humidity: None/low
Terrain: Low, rolling hills
Distance: 3 miles

What I wore: Knit hat and gloves, neck gaiter, Nike tank-style sports bra and heavy-weight technical shirt with cuff pockets, Illuminite wind-resistant jacket, CW-X compression tight, thick dri-fit socks.

Did it work: Yes, except my hands were cold. I'm now looking for gloves that have a wind resistant material on the outside. When I find something I like, I'll share it here.

Tip: Start adding layers from the top down. As long as your extremities (head, hands and feet) are warm, you don't have to worry too much about bulking up on the bottom, at least until the weather gets really nasty. More layers on top paired with thick tights will get you through a surprisingly wide range of temperatures.
For the ladies: To add layers without feeling like the Michelin Man, wear a tank sports bra. The tank gives you an extra layer over your core, which, after hands and head, is key for body temperature control. The tank is also nice because the close fit keeps out drafts on windy days.