There are two main seasons in Peru – the wet season and the dry season – and three main climatic zones: the tropical Amazon jungle in the east; the arid coastal desert to the west; and the Andean mountains and highlands in the middle of the country. Essentially, while the weather varies from region to region the temperature is mostly influenced by elevation: the higher you go the cooler the weather.
Rain is common year-round in the Amazon rainforest, however the wettest months are mid- November to March and even in the wet season it only rains for a few hours at a time. The rainforest also enjoys quite hot weather ranging from 26°C to 40°C, with the cooler months from April to November.
The coastal region is where the locals head during the hottest months from mid-November through to the end of March. Rain is most likely to fall along the coast between June and October, however is infrequent. The cold weather along the coast generally lasts from the middle of April until November. Temperatures along the coast are pleasant (14°C to 28°C).
The highlands are cool, averaging between 9°C and 18°C because of the altitude, but can be visited year round even during the wet season which falls between December and March.