Safe in Extreme Cold?

[PortableTV]

I've built a little collection in my garage here where it's 20 degrees outside these days. Probably around 30/35 degrees in the garage.

Question - Is it safe to turn my CRT's on in such cold?

Normally when I hang out there I put on a couple of space heaters for a couple of hours before turning them on but I was just curious about any risk associated with cold weather power-up...