Sumatra in August

June through September offers the driest conditions, though 'dry' is relative when you're this close to the Equator. Humidity stays high year-round, but you'll get fewer afternoon downpours during these months. The western coast sees less rain, while the eastern lowlands stay wetter longer. October through May brings the monsoon, with December and January seeing the heaviest rainfall. But here's the thing — rain in Sumatra often means short, intense bursts followed by sunshine, not all-day drizzle. Wildlife viewing actually improves during shoulder months like May and October when animals come out more frequently to drink and feed. Lake Toba stays pleasant year-round thanks to its elevation, while highland areas like Bukittinggi and Berastagi offer cool relief from coastal heat. Avoid major Indonesian holidays like Lebaran when transport gets packed and prices spike. Dry season also means better road conditions for reaching remote areas, though you'll pay higher accommodation rates in popular spots like Bukit Lawang.