At what temperature do you stop running outside?

For me, I run indoors if the windhill or temp is -10 or colder.  The early darkness is more of a factor for me as I fear turning an ankle on some uneven snow or ice.

I stop running below 0, although I was kind of wimpy last year.  There was so much persistent ice I just got tired of it.

I've been working on winter riding and have done about 20 degrees I think.  I was surprised by how comfortable I could make that with the right gear.  Again, just stymied by the ice.

Chris - you are kind of a wuss.  You seem like a really nice guy and I didn't want to have to say it

It doesn't have to be in the dark, I stick to weekend days mostly.    In particular I like the LRT trails with the trees surrounding you covered in white. It makes me appreciate the few gifts that living in a wintry climate brings.  Once you figure out which layers work best it's very easy to get comfy, especially on the trails which block the wind.  Often (not last year...) the paths are cleared before the roads!  Awesome.

Some of my favorote runs are around Calhoun and Harriet with a group of BT'ers in the middle of winter.  I won't ride outside if there is a hint of ice or heavy frost.  I've had one bad crash and do not look forward to the healing process again.

I love running outside in all weather. If it is to icy I don't run outside, I go to the treadmill. I actually do less true running in the winter and do a lot of snow shoe running. I have a nice golf course right next to my house that is completely untouched in the winter. It is like my private park. My dog and I go out almost everyday snow shoe running. I bought an LED headlamp for myself and a lighted dog collar for the dog and we go out at night too. I actually am looking forward to the cold and the snow of winter.

I have run in -30 degrees before, so I guess that was my limit.  I had a chest cold for weeks!  On the flipside, I have run in 115degree temps too!