All year round crystal clear warm water. Fringe reef with about 3-5 ft deep water during high tide. Huge area which allows approximately 2 mile x 500 yard area to ride in. Watch out for shallow areas and the small, low lying island in this area. Shoes are recommended due to the reef. Tidal beach. Be careful with other water activities and swimmers.
Works in WNW and North directions. Dry Season is December to June with 15-20 knot trade winds. Wet season winds are intermittent at about 10-15 knots. Trade Winds are normally out of the East. Guam is an Island so it pretty much does not matter which way the wind blows since there are multiple spots to kitesurf around the whole island.
A rental car is best option to get around. Cars can be rent right from the airport. Buy a map and just look for Tumon Bay which can be seen from the airport. There are good launch sites near the Hilton and Holiday Inn hotels although other places can work as well.