Being a tropical country, Indonesia is blessed with two seasons, namely dry and rainy. Dry usually occurs from June to September and the rest is rainy season. Sunshine is abundant except in rainy season when the sky tends to be cloudy. It is advisable to visit Indonesia during dry season.
All of the Indonesia islands in the archipelago lie within the tropical zone. Generally, the weather is hot and humid. Indonesian climate is divided into two distinct seasons: dry and rainy seasons, and the surrounding seas exert everywhere a homogenizing effect on temperatures and humidity, so that local variable like topography, altitude and rainfall produce more variation in climate than do latitude or season. Mean temperatures at sea level are uniform, varying by only a few degrees throughout the region, and throughout the year (25-28 C/78-82F). In the mountain, however the temperature decrease about one degree C (two degrees F) for every 200 metres; 656 feet) of altitude, makes for a cool, pleasant climate in upland like Bandung (in West Java; altitude 900 metres ;2,950 ft) and Bukit Tinggi (in West Sumatra; altitude 1,000 metres ; 3,280 ft).
Much of the archipelago also lies within the equatorial ever wet zone, where no month passes without several inches of rain fall. Most islands receive considerably more than this during the northeast monsoon, which blows down over the South China Sea picking up moisture, then veers to the north west across the equator, unleashing drenching precipitation wherever it touches land from November through April. Moreover, the tropical sun and the oceans combine to produce continuously high humidity everywhere, and due to local wind patterns, a few places like Bogor in West Java, receive rain almost daily –as much as 400 cm (200 inches) of it anually. 
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