The weather in Ecuador is exceptionally difficult to predict. There are virtually countless microclimates due to extremely varied topography that cause varied weather in neighboring geographical locations.
One generalization that can be made is that the temperature is usually colder the higher the altitude. Still, people in Quito and much of the Andes have a saying, "We have four seasons in a single day." Although the temperature does not vary much throughout the course of the year - the country does straddle the equator - Ecuador's rainy season coincides with winter months in the northern hemisphere.
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These two currents cause only one rainy season on the Coast which intensifies in March. In the mountains, it causes the months from March to June to be rainy and from October to December to be another rainy season. In the amazonia, they cause only one rainy season that is uniformly rainy throughout the year. The topography of the Andes causes climactic changes in the mountain region; as you go higher, it gets colder by about -4.70 C for every thousand meters.
There are two opposing marine currents that influence the climate of Ecuador. From December to May, the warm current of El Niño coming from the north occurs in the Pacific ocean and for the rest of the year, the cold Humboldt current comes from the south. When one of these currents becomes stronger and persists longer than normal, there are variations in precipitation on the continent. If the El Niño current is stronger than the Humboldt current, the rains on the continent increase causing floods. If the Humboldt is stronger, the rains decrease causing drought.
The islas galapagos
Weather in the islas galapagos is largely determined by ocean currents. Normally from June to December, the cold Humboldt current comes from the South and creates an inversion that traps a cool moist fog called a garúa near the ocean which creates a cool, dry climate. Typically in December, the trade winds die down and the ocean currents change, bathing the Galapagos in the warm Panama Current from the North. The warm currents bring about a typical tropical weather pattern: hot sunny mornings followed by clouds and occasional showers in the afternoons. Use the following as a rough guideline.