Check out Typographic Temperature Technicality by rogersgeorge. Here is an excerpt:
Did you know that you don’t use the degree sign when you write the wind chill?
Here’s the whole paragraph:
With the new [as of 2001] formula, Environment Canada began reporting wind chill as an index stripped of units, so that a calculated wind chill of, say, -30°C is communicated…
The full article is available here.
