Hot hike.  Day started off early, arrived at the park at 7:30am, and started hiking at 7:45am.  Temperature was in the mid-60's at this point.  I've hiked Mt Sizer a few times before, but this was the first time to do the Loop.  Bugs were out early, pretty annoying.  Around noon, it got really hot.  My watch reading was saying above 101 at one point.  I carried a lot of water (3L bladder, 40oz water bottle, and two water bottles) and that was barely enough.  Only saw one person for most of the hike, not counting the people at the start/end of the trail.  Would have been so much nicer (and manageable) if the weather was 20 degrees cooler.