Trips starting in Cajamarca and Huaraz: Cajamarca and Huaraz are cities high in the Andes mountains. It is generally warm and sunny throughout the day, then quite cool at night. You will need pants and a sweater or jacket to be comfortable in evenings. Trips finishing in Jaén: Jaén is a warm, humid city. You will not need a sweater or pants to be comfortable here. Add on trips: If you are heading to Chachapoyas on a Kingdom of the Clouds add-on the weather can be quite varied. From warm and sunny through the day, to the odd rain storm to cool and fresh in the evening. You should prepare for all types of weather, including shorts and t-shirt for hikes, pants and sweater for evenings and cooler days, and bring a raincoat.