How cold is it?

I ran this morning - -21C (I deliberately didn't listen for the wind chill - sometimes it's better not to know). Part of the group I trained with for Long Beach are also running the Honolulu marathon. Today was their 4 hour run, so knowing how much fresh people with new conversation are appreciated half-way through a long run, I decided to join up with them at that point. So with two layers of tights, 3 layers of shirts plus my jacket, my down ski mitts and MH's toque, I went out. After 10 minutes of waiting, I went off alone (I was getting cold) - and met them as I was coming back (I did an out and back run). The good news? I RAN (always important to feel smug) - if I had known that I would not meet up with them until 50 minutes into my run, I likely would have stayed in my jammies. But the fact that I was there, dressed and ready, meant it was a foregone conclusion that I would run. I usually feel strong and proud of myself for running anyway - but when I run in these conditions, it's like a huge shot of self-worth, wrapped up in a box and tied with a bow. The bad news - I wiped out - running by the river is always a little tricky as things tend to be icier. I don't think I have done any permanent harm, however - too many layers and the fact that I was running in the cold meant I didn't really feel it anyway - at least until now.