In a perfect world, I’d walk, hike, or run outside every day of the year. Fortunately, Colorado’s weather is nearly perfect—except for last week.

I grew up in the tundra North Dakota, so I can handle plunging temps, but even I know when it’s best to stay indoors. There are certain temperatures (say, below 20) that are too dangerous for me to venture out in. Sure, I worry about exposed skin, but I stress out more about the drivers who aren’t expecting pedestrians and