How are the night time temps in Acadia in late June? We were wondering if a simple sleep sack liner will do or if we should pack up our 3 season sleeping bag. I read day time temps vary but in the 80s that time of the year - not sure how cool it gets at night though since summer temps along coastline tend to be cooler. Also are bugs a major issue or do the birdies take care of that well? Thanks!