condition mean min max 4 h after light 631.6 631.6 631.6 8 h after light 769.35 614.1 924.6 12 h after light 686.25 623.4 749.1 4 h after dark 778.0 749.1 806.9 8 h after dark 863.9 821.5 906.3 12 h after dark 860.25 755.6 964.9