For the sea kayaking portion of the trip in Curu, temperatures tend to be warm with a very low chance of rain. Wind is possible. Typical beach attire is appropriate, along with one warmer long-sleeve layer for mornings and evenings.
During the river and jungle portion of the journey, the temperatures during the day are generally warm and cool in the evenings. A light pair of long pants and a warm top such as a fleece are recommended, as well as a good rain jacket. Rain is possible throughout the year, and cooler daytime temperatures tend to come with rainy days.