These islands vary in size, appearance and topography. Following World War II the U.S.A. administered these islands as a trust territory under the United Nations. Micronesia has some of the most uniform year round temperatures in the world. Temperatures range between 21 and 32 degrees Celsius, with the average daily temperature for all of Micronesia of about 27 degrees Celsius. Winter months, with the lowest rainfall, are January to March.
Diving is possible all year round although the visibility varies.
Best visibility is found from October to May when the northeast trade winds clear the plankton rich water. June through September is the rainy season and the calmest time of year. Guam located just 13 degrees north of the equator, is the westernmost U.S. territory and undoubtedly Micronesia's most cosmopolitan destination. The marine habitat is rich and lush with more than 800 species of fish and 300 species of corals. Not far off shore is the Marianas Trench -the deepest spot in the world.