It pulls less hard on the Earth, but even less hard on the water on the far side, so a watery bulge forms on the far side as well -- a high tide roughly 12 hours out of synch.

CNN: The sun, the moon and the Titanic

We're recommending that people in areas that have experienced coastal flooding to evacuate three hours before high tide.

NPR: Late-Winter Storm Sweeps Into New England

Rescue attempts were delayed by two-and-a-half hours because of the high tide which peaked at 2030 GMT, only a short time before the accident.

BBC: Inquiry into four river deaths