condition mean min max 4 h after light 688.8 688.8 688.8 8 h after light 876.65 668.3 1085.0 12 h after light 912.05 846.1 978.0 4 h after dark 774.45 677.0 871.9 8 h after dark 586.7 557.7 615.7 12 h after dark 562.4 480.8 644.0