Traveling to Peru in July (2013) was my first trip to South America! It was also my first time below the equator, and therefore shifting from summer to winter back to summer over a two-week period. Since Peru is close to the equator and therefore the winter is more of a dry season than ‘winter’ as I’ve come to know it (raised in Michigan and now a New Englander). As one might expect, the climate is different depending on whether you visit the coast (Lima) or inland (Arequipa, Cuzco, Sacred Valley). Our trip began in Lima; a city that I would suggest does not have a dry season, but a damp season and is overcast for 8 months of the year. When I say overcast, I mean that you will not see the sun – at all. There was a light drizzle/mist every morning; it remained overcast all day yet surprising to me, there was not a drop of rain. I inquired about the weather and the chance of rain with several Peruvians and found that our experience was the norm. The lack of rain was affirmed with my observation that Peruvians do not wear raincoats and no one carries an umbrella. The temperature during the day is mild (upper 50’s and 60’s), but the dampness makes it feel a bit colder. The temperature in the evening drops slightly, but it never gets cold there.
Arequipa’s and the Sacred Valley’s (Machu Picchu, Ollantaytambo, Cuzco, etc.) weather patterns are fairly similar to each other and very different from Lima. Again I wouldn’t consider this winter, but the very, very dry season. It will not rain, nor is there any dampness as in Lima (sans Aguas Calientes). Be prepared for an uncomfortable dryness in the air, especially while sleeping. To anyone else who has spent their life fighting frizzy hair in high humidity, a word of advise: drink a lot of water before going to sleep and have a full water bottle for each person. There were several nights that my husband and I decided to share one water bottle and one of us woke bone dry at 1 am only to realize the other had already finished it off. Since in Peru you can’t drink the water from the sink, this predicament leads to hours of discomfort and angry mumbling toward one’s travel companion. =/ Bottled water is easy to come by in all areas, except in the middle of the night, so always overestimate how much you will need.
I digress…during the day, the sun is bright and it is warm. If I were in Boston, I would definitely wear shorts, yet Peruvians are all wearing pants. It is warm and dusty – really, really dusty! If you are in a city center it won’t be too bad, but if you end up anywhere else, be aware of this. (I am speaking to anyone that wears contacts or has a dust allergy…like me. Consider packing Visine and sinus medication. Also, bring a lens cloth for your camera.) Now the evenings are a completely different story. The temperature DROPS! Cuzco is at a higher altitude so it will get significantly colder than Arequipa, so bundle up. This is where I bought a pair of alpaca mittens and considered a hat as well.
Despite being located very close together, the weather in Machu Picchu and Aguas Calientes were quite different due to the altitude and time of day that we were in both locations (Note: Aguas Calientes is the small city from which you travel up the mountain to Machu Picchu). One can only visit Machu Picchu during the day, and since that’s where you will spend your day, you will most likely be in Aguas Calientes in the evening only. If you go to Machu Picchu as the sun is rising (which is awesome!), it will be chilly, but bearable. The afternoon gets very hot and sunny! Given the name, Aguas Calientes (Hot Waters), you can correctly infer that it will be damp here, but again, it will not rain. It gets a little chilly in the evening, but not as cold as Cuzco or Arequipa (no mittens needed). =)
Overall the weather in Peru was quite lovely – not too hot, nor cold, nor wet, just a little too dry.