Right now it's about 28 to 40*F in the mornings, and wet. At 40, I'm wearing bike shorts, a long sleeve compression top, some loose, cheap lined nylon running pants (with a velcro band on the right ankle), and a waterproof, vented rain jacket, waterproof breathable gloves, wool socks, a helmet cover and I have a poly stretch tube of fabric from Nashbar that I put around my neck then stretch it over my head before putting my helmet on, so only my face sticks out.
At 30, I add a T-shirt (poly, alertshirt).
At around 25 or so I'd add some running tights under the pants.
At 15-20 I'd start thinking about wrapping a fleece scarf round my neck so that the ends covered my chest.
Down around 5-10 I'll wear long underwear (cotton, I'm too cheap to go buy good stuff) over the poly shorts and tights, under the pants. Wool would be better but I haven't needed it.
At 0-5 I'll add some kind of insulated shirt.
I do run a bit cool, but I like it like that. Generally my core temp is up but my skin is pretty cold when I get there. I don't feel cold, but the warm shower feels quite hot and my skin on my torso feels chill to my hands.
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Work: the 8 hours that separates bike rides.