In summer high temperatures are usually over 100F = 38C (sometimes even 110F = 43C), low over 70F (21C).
More: Weather Station in Tacna
Check the 10-day forecast for Yuma (46 miles = 74 km west of Tacna):
National Weather Service
My top 5 advices:
1. Wear very light (and too large :-) clothes made of natural materials (cotton) and a hat,
2. stay in shadow if possible and move slowly hehe,
3. drink a lot of cold water (no sweet juices or booze),
4. avoid midday and early afternoon,
5. keep smiling :-)))
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Visit southern Arizona and Tacna from November to April.









