How do El Nio and La Nia affect our weather?
The periodic changes in the Pacific Ocean water temperatures that define El Nio and La Nia can impact weather patterns around the world. The effects are more prominent in countries surrounding the Pacific Ocean and are most noticeable in the winter and summer months. During El Nio episodes, drier-than-normal conditions can affect much of South Asia and Australia while wetter and warmer-than-normal conditions occur across southern and western South America. During La Nia episodes, wetter-than-normal conditions can last for many months across South Asia and Australia while cooler-than-normal weather prevails in parts of South America. In Canada, El Nio’s impacts are most clearly noticed during winter in western Canada. While the southern United States sees cooler and wetter conditions, western Canada often experiences mild winters during an El Nio episode. Depending on the strength of the El Nio, milder-than-normal conditions may extend through Ontario, Quebec and towards Atlantic Canada
