Weather locations in Peru

Peru contains almost every climate on earth except permanent ice: a dry Pacific coast, a cool Andean highland, and a hot, humid Amazon rainforest behind the mountains. The cold Humboldt Current and a rise of nearly 4,000 metres within a few hundred kilometres produce this contrast.

Main climate types

Three great zones run parallel from north to south. The coast is desert or steppe in type, and because the cold Humboldt Current suppresses rain, most of it takes under 100 millimetres a year; Lima sees almost no rain at all in the southern summer. East of the Andes the Amazon basin is tropical rainforest, with rain in every month. Between them lie the Andes, where the mean temperature falls by roughly 6 degrees for every 1,000 metres of elevation.

Temperatures

Lima averages about 21 degrees in January and 17 in July, with cool foggy mornings and mild nights, and the sea stays near 19. Up in the highlands, Cusco at 3,400 metres averages about 13 degrees in January and 9 in July, with hard frosts on clear mornings. The Amazon city of Iquitos averages about 26 degrees year round, with highs in the low 33s and nights rarely below 22.

Rainfall

The coast is effectively rainless outside winter, recording only a few tens of millimetres a year, and the southern coastal deserts occasionally go seasons with almost nothing. The Amazon side takes over 2,000 millimetres, with the wettest months usually from December to March. The highland puna gets most of its rain from November to March, and snow can fall on the Altiplano in that season.

When to go

On the coast June to September is the dry, clearest season, though winter there brings persistent grey drizzle and near-freezing mornings. In the highlands, May to September is dry and clear, the best time for the Inca Trail and for the lakes around Cusco. The Amazon is greenest and the rivers fullest in the wet season, generally from January to April, when boat travel is easiest.