It's chilly out there

I usually consider 30F my low threshold for cycling. Below that temperature, I often don't feel like putting on enough layers to ride. I trust my bicycle to not have mechanical failures (more a trust in myself as a mechanic for preventing them), but still have concerns over how I'd deal with, say, a flat tire (something that requires a bit of dexterity) in sub-freezing temperatures. Even so, with reported temperatures in the high 20s, I rode to work today. I had to push myself out the door, but I rode. I had one more layer than I did yesterday, everywhere but on my feet. I couldn't find my shoe covers last night or this morning, and my girlfriend reminded me that she plans to repair the left one where a seam ripped last season. Plan B for tomorrow is to wear two pairs of socks, a pair of Gore-tex shoe liners, and my sandals (since I can open them a bit to allow for the extra bulk). All that in shoes would cut down circulation, and make my feet even colder. The other key to keeping my feet warm is keeping my legs warmer still, and I may add a wind layer to aid that process.