Peru is different from most other countries because it has three distinct geographical regions which are long narrow strips of land, running north-south:
1) The Pacific coast
2) The Andes and mountain highlands
3) The Amazon jungle
It’s easiest to think “two seasons” (wet and dry) rather than “four season”.
1) The Pacific Coast (Lima, Nazca and Arequipa). Sea level.
December – April
Summertime: it’s hot and dry and ideal for swimming and getting a tan! Temperatures range from 25 – 35°C and there’s no rain at this time. The beaches around Lima and the North can get packed during the months of January and February (school holidays).
May – November
The temperature drops a bit and you’ll find blankets of sea mist known as garúa engulfing the coast from the Chilean border in the south right up to about 200 km north of Lima. At this time of year only the northern beaches such as Mancora and Punta Sal are warm enough to enjoy swimming.
2) The Andes and Mountain Highlands
(Cusco and Lake Titicaca, the Altiplano). Around 3,000 to 3,500 m. Peaks reach above 6,000 m.
Mid April – October
This is the dry season with hot, dry days and cold, dry nights hovering just above freezing, particularly in June and July. May is perhaps the best month because the countryside is lushand the air clear and dust-free giving excellent views. Flowers are in full bloom, the grass green and the streams full.
Peru’s high season is from June to August which coincides with the dry season and summer holidays in North America and Europe. Cusco is a pretty cosmopolitan city with tourists from all over the globe converging on Machu Picchu.
November – Mid April
The wet season with most rain in January and February. It’s usually clear and dry most mornings with outbursts of heavy rain in the afternoons. The daily temperatures are typically mild with only a small drop at night.
The Inca Trail is much less crowded during this period (though it’s closed in Feb) and you will need to be equipped for the rain. You’ll also find some roads may become impassable particularly when trying to visit villages off the beaten track. Many of Peru’s major festivals such as Carnival and Easter Week take place during this period.
3) The Amazon Jungle. 1,000 m and lower
April – October
This is the ‘dry’ season with daily temperatures averaging 30–35°C. However cold fronts from the South Atlantic are not uncommon and temperatures can drop to 15°C during the day and 13°C at night.
The dry season is the best time to visit the jungle because there are fewer mosquitoes and the rivers are low, exposing the beaches. It’s also a good time to see nesting birds and to view the animals at close quarters because they come down to the rivers to drink as water supplies decline.
November – March
Wet season: hot and humid, expect heavy rain at anytime but it only rains for a few hours at a time, so it’s not enough to spoil your trip; follow the locals’ example: briefly take cover during the heaviest downpours. It’s not a big deal. Wellington boots are a must because jungle trails can become small streams!
The El Niño effect, which occurs on average every seven years, is when large-scale changes in ocean currents and rising sea-surface water temperatures bring heavy rains and floods to coastal areas, plunging tropical areas into drought and disrupting weather patterns worldwide. The name El Niño (literally ‘the Child’) refers to the fact that this phenomenon usually appears around Christmas. The El Niño in the winter of 1997–98 was particularly traumatic for Peru. El Niño is usually followed the next year by La Niña, when ocean currents that cool abnormally create even more havoc and destruction.