You will be fine. Wood changes moisture content very slowly in air, and any dimensional change that occurs in an object the size of a plug is going to be nearly imperceptible. Your tools will rust, however, if there is condensation on them.
Location: Jackson, NJ but born and raised in Massachusetts.
Posts: 1,223
Keep a close eye on your machines. It sounds like an evironment that will promote rust.
I suggest that you cover your head and tail stocks with an oily rag. Poke it in the taper to keep the rust out. If then tapers become pitted they will not hold.