For diving with dugongs and turtles in Marsa Mubarak, spring, autumn and winter are usually the best choice. In those periods, diving often feels more comfortable and the day is less tiring than in the hottest months.
Why these months often work better: - the water and air are usually more pleasant - you are less affected by extreme heat before and after the dive - the day is easier to keep up for - it fits well with a relaxed bucket-list trip to Port Ghalib
Outside this window, the experience can still be good, but the conditions are often less comfortable. Heat, crowds and fatigue can weigh more heavily. If you are coming for the nature experience, it is best to choose a period when the diving itself can stay central.