Canada may be spared from its typically brutal winters this year due to the emergence of an El Niño event that should bring milder conditions across the country.
El Niño is a recurring weather pattern that involves surface waters in the eastern Pacific Ocean (extending westward from Ecuador) becoming warmer than average. As a result, the earth's natural atmospheric circulation undergoes a shift, with the reversal of westward trade winds suppressing the usual upwelling of cold waters.
This causes normal weather patterns in various locations across the globe to change temporarily, with colder areas becoming warmer, drier areas becoming wetter, and visa versa.
The U.S. National Weather Service's Climate Prediction Centre (CPC) recently increased the probability of an El Niño occurrence to 65% for fall and 70% for winter this year. While the U.S. is more prone to extreme conditions such as cold snaps, crop damage, fires and flash floods during El Niño periods, Canada is more likely to experience milder-than-normal winters, especially the western, northwestern and central regions.
"The forecaster consensus favours the onset of El Nino during the Northern Hemisphere fall, which would then continue through winter," the CPC says.
As for Eastern and Atlantic Canada, such regions are not known to be significantly impacted by El Niño events, however, they may still see a reduction in tropical cyclone activity.
One of the strongest El Niño events to hit Canada was during the 2015-16 winter season, which caused all provinces to become one- to five-degree Celsius warmer than normal. The Prairies, Quebec and Yukon were especially warm, with winters exhibiting milder temperatures for that year.
If that's any indication of how this year's El Niño event will impact Canada, then we can expect a more comfortable winter ahead.