El Ninos recur every three to eight years, and it has been a few years since the last one. El Nino begins as a giant pool of warm water swelling in the eastern tropical Pacific Ocean, that sets off a chain reaction of weather events around the world – some devastating and some beneficial.
A strong El Nino is often associated with flooding rains and warm weather in Peru, drought in Indonesia, Africa, and Australia, torrential downpours and mudslides in southern California, a mild winter in the northeast, and fewer hurricanes in the southeast. Keep in mind that these effects aren't guaranteed, but an El Niño makes these conditions more likely to happen.