They'll get a bit of nice colour and that's about it probably. Most strains can handle anything up to a killing frost, especially if the days are nice - which they certainly have been. I just returned from a cycling trip in Oregon. I couldn't help thinking what a paradise for ganja growing it must be. It hit 100 F our last day there.
Yup color change for most. Kicks em into gear. The onset of winter stimulates increased trichome production. The thc glands/stalks are made to protect the seed or would be seed (nonpollinated swollen calyx) through the winter creating a layer of resin surrounding them. They will respond nicely to the cold nights.pick up a $10 mini light microscope from radio shack to inspect trichs for peak chop dates. They are hardy plants able to withstand even light snows so... Harvest is near. Enjoy