The best time to dive in Mexico depends on which liveaboard diving destination you want to visit. The Sea of Cortez is open for liveaboard diving from July to October, with September to November being the whale shark season. In Guadalupe the season is July to November, when the great whites gather around the island to feed on elephant seals. Socorro is at its best between November and May with whale shark season around November and December. It is worth noting that the water temperature makes a short drop to 70° F (21° C) in February and March.