I, on the other hand, have been disappointed with how hot it has been for September in Colorado, because I just divided a bunch of perennials hoping cool weather was imminent so they'd have an easier time establishing. 80-degree weather is not great for plants stuck into the ground with hardly any roots. I think I lost some of the oriental poppies I took root cuttings from and some of the other plants are looking pretty sorry.

Anyway, I'm in Colorado also, growing brugs indoors and out.

Are yours in pots? If so, and if the "big freeze" comes and they are still blooming or have not yet bloomed, they will be perfectly happy to continue blooming in the warm house for a couple more weeks until finished. If you can set one in front of a sliding glass door, that's great. But even if you don't have the best light, they will continue blooming until the current crop runs its course, then they will return to a more vegetative growth or start going dormant.

A full crop of brugmansia flowers in the house has a very intense scent that penetrate absolutely everything at night; its pretty intoxicating.

I've put them in the garage before and they kept putting out new flowers in total pitch-black darkness for about 3 weeks. First, the leaves dropped. Then the newly-opening flowers became smaller and paler, until finally the remaining small buds dropped and the plants went dormant. It didn't seem to hurt them at all and they happily came out of dormancy in the spring.