El Niño vs. La Niña: The Canadian Weather Explainer
What is the difference between these two ocean phenomena, and how do they determine our Canadian winters?
Understanding ENSO and its influence on our local climates.
The El Niño-Southern Oscillation (ENSO) is a cycle of warming and cooling in the eastern tropical Pacific Ocean. While it happens thousands of kilometers away, it dictates storm tracks and jet stream patterns directly over Canada.
El Niño: The Warm Phase
During El Niño, warmer ocean temperatures shift the jet stream south. This typically brings milder-than-normal winters to most of Canada, with less snowfall in Ontario and Quebec, and dry conditions in Western Canada.
La Niña: The Cold Phase
Conversely, La Niña is characterized by cooler waters. It pushes the polar jet stream south into Western Canada, bringing freezing cold Arctic outbreaks and abundant snowfall to British Columbia, Alberta, and Ontario.
