An El Niño has formed amid the warmer-than-normal waters in the tropical Pacific. Now it's a question of how intense the phenomenon will be, and where effects like heat and drought will strike.

No two El Niño events are exactly alike, though forecasters have a pretty good idea of what’s likely to happen

How the cyclical weather pattern interacts with climate change could spark food insecurity around the world.

An El Niño event occurs when the ocean becomes warmer than usual, affecting rainfall and wind patterns.

An El Niño has formed amid the warmer-than-normal waters in the tropical Pacific. Now it's a question of how intense the phenomenon will be, and where effects like heat and…