Wow, learned first hand how rapid climate change affects a guitar neck. I'm an Illinoisan; our winters are typically cold with low indoor humidity. Took a trip to Florida for two weeks and had really warm outdoor temps and a hotel room w/cranked air conditioning. Within two days of arriving, my axe was unplayable; fretted out on the two closest to the nut. I had my string action set really low and it took loosening the truss rod nearly 3/4 turn over two days to make it playable. I'm back home now re-acclimating in the other direction; basically performing a total setup. I suppose this is a routine task for professional bands touring the country.