haha, that's why we live in New England!
Most of our spring/summer/fall shows are outdoors here in the northeast. It's much cheaper for the club, and the weather is usually pleasant. We get rained on some weekends and cooked in the sun on others, but we don't really encounter deadly levels of heat like they do down south. Dog shows go on rain or shine - they generally do not cancel, unless the weather is truly life-threatening.
Also, I don't think there exists a dog who doesn't look much lovelier in natural light than in a building!