Any time of the year is perfect for visiting the Ecuadorian Amazon since the weather varies only slightly from month to month in both rainfall and temperature. Expect some rain (it is the rainforest after all!) but you’ll likely have similar periods of bright sunshine. In general, it’s hot and humid, but not as much as many people imagine.
The year-round temperature average is 82°F (28°C), however, nights can be cooler. Since Ecuador is located right on the equator, the country does not experience extreme weather changes aside from a slightly rainier and wetter season. During a visit to the Amazon region, in a 4 or 5-day visit, you will often see more or less the same amount of rain and sunshine.
The Rainier Season in the Amazon
Runs from December
, with temperatures ranging from 23°C (73°F) to 30°C (86°F) and frequent rains throughout April and May. The Rainy Season has its pros due to the fact that many plants have evolved to fruit and flower during the rainy season - a phenomenon which often attracts birds and primates to the water's edge and grants visitors the chance to observe them more frequently.
The Drier Season in the Amazon
Lasts from July
, with temperatures from 26°C (78°F) to 40°C (104°F), with less rain, though showers are still possible. The Dry Season also offers its own set of benefits, for it's during this time that the water gets lower and attracts animals that you won't often see during the rainy season. Beach nesting birds are everywhere, as there are more beaches present during this time. Fish also tend to lay their eggs during this period of lower water levels, and as a result, you'll often see them swimming around fervently in the shallows of the rivers. Consequently, birds go on a feeding frenzy with the abundance of fish and you'll often see all kinds of birds flying or muddling about these riverbanks. It's important to note that the Amazon Crocodile (known as Cayman) is much more prevalent during the dry season, and will usually be found nesting while feeding off the abundance of fish.
Current Weather: http://www.worldweatheronline.com/Coca-weather/Orellana/EC.aspx