My first time growing moonflowers. Have been watching this bud for a few days. Starting showing signs of unfurling at about 5:30 pm. Has a lovely mild fragrance. (I had to take the later picture under an umbrella.) Here's some cultural information: http://www.localharvest.org/blog/48630/entry/everything_you_wanted_to_know1
Update: Just went out (around 10pm) to see if the fragrance was more intense after it was totally dark out. Wow, was it noisy!
No...the fragrance was still very light.
(Sound was recorded by the E-PL5 in video mode - I stripped off the video in Sony Vegas Movie Studio to save it.)