A Warm Sleeping Bag is Always a Good Idea
When I bought a sleeping bag rated to -15 degrees, it seemed like real overkill. After all, Australia has never, ever recorded a temperate that low (-9.4 at Charlottes Pass on 29 Jun 1994 is our lowest ever recorded temperature). Camping up at Mather Camp Ground on the South Rim of the Grand Canyon on my first night in the States, it seemed very cold. The next morning, I was having breakfast in the Marketplace dinner, and they mentioned it got down to 7 degrees. It seemed a lot colder than that, until I mentally switched over to farenheight. 7 farenheight is -14 celcius, and it was a bit cold even in the -15 rated sleeping bag. I was trying to set off my flash in the tent during this shot, and managed to drain 12 AAA batteries during the exposure.
[Update: The -9.4 at Charlottes Pass was in farenheight, which is -23 celcius, so the sleeping bag wasn't that extreme after all]