condition mean min max 4 h after light 700.3 700.3 700.3 8 h after light 758.15 677.0 839.3 12 h after light 708.45 703.2 713.7 4 h after dark 751.85 732.6 771.1 8 h after dark 602.7 548.5 656.9 12 h after dark 464.2 459.7 468.7