For two nearly identical runs on consecutive days , I could not have had more different experiences. The route was 95% the same. Yesterday was -20C and sunny; today was -10C and sunny. The big difference today, probably resulting from slightly warmer temperatures, was the footing. Yesterday the colder temps and the wind kept the snow hard, and the traction was great, especially on the est side of the Canal where the sun activated the salt. Today it was like running in sand, and really, really frustrating.
I heard that there is 52 words for snow and ice in Inukitut. I am starting to understand why. Today the snow was soft and mushy, but not necessarily slippery - there is probably a word just for this kind of snow. The problem with running in it is that it is nearly impossible for one's foot to land or push off properly. The only clear spots were under bridges, and those sections were only long enough to bang the snow off my shoes. I don't know when I have worked that hard to run that slow.
The other problem was that I was over dressed today and I over heated. On both days I wore my Paradox merino wool top and bottoms for a base layer and Mizuno Breath Thermo socks on my feet. The merino wool ensemble was really cheap at Costco ($45 for both pieces), but it is amazing. I seriously recommend picking it up for anything you do outdoors in the Winter. I wore a long sleeve tech shirt and the Brooks Storm jacket yesterday, which worked great. I wore the same shirt and the mystery Lululemon jacket today and it was way too much. With a 10 degree difference in temperature I should have left the tech shirt and neck gaiter in the bag and maybe gone with a lighter jacket. Live and learn, I suppose.