I have the same temps as you do and I decided to cut my girls down yesterday around 3:30 Pm well let me tell you it took me until 11:00Pm to trim all my plants buds. I know I had some that were not quite ready but I was not taking anymore chances......The answer to you question if frost kills your plants NO you really can't bring it in and do anything with it cause it will be all mush. If your plants lived through the night I would pull tonight as it is going to get colder and I hear snow is coming on tuesday. (Looks Like we live close to each other)