The only thing predictable about Ecuador's weather is its unpredictability. In fact, it's not uncommon to experience all four seasons in a single day. Generally speaking, Ecuador has two seasons, wet and dry, but in a country as geographically diverse as Ecuador, local weather patterns vary greatly.
The mainland coastal areas and the Galapagos Islands are influenced by ocean currents and are hot and rainy between January and April and cool and dryer the rest of the year.
In the highlands, the dry season is between June and September and around Christmas, but even the mountains' wet season isn't particularly wet and the dry season sees its share of downpours. The central valley is generally spring like year round, with mild temperatures around 24°C (66°F).
The Oriente (Amazon) experiences... you guessed it, rain, heat and more rain and heat! The average daytime temperature is 30-32° C (85-90° F), while nights can cool down to 20° C (68° F). The least rainy period tends to be January to May. June, July, and August are the wettest (still considered a prime time to visit the Amazon because of increased animal activity), and September through December are completely unpredictable! Our advice, expect rain and heat year round!