![\"A](\"https:\/\/www.newsbeep.com\/ca\/wp-content\/uploads\/2025\/10\/eccc-sea-surface-temperatures.jpg\")
A large and unusually warm area of water in the northern Pacific Ocean on Monday is shown in this graphic from Environment and Climate Change Canada. (Environment and Climate Change Canda)<\/p>\nMany Canadians experienced decidedly un-fall-like weather last weekend, with temperatures soaring into the mid- to high-20s across many parts of the country \u2014\u00a0well above seasonal averages.\u00a0<\/p>\n
People flocked to beaches in Toronto and Ottawa, an unlikely sight for the beginning of October, as the nation’s capital broke a heat record,\u00a0reaching 29.9 C on Sunday. Montreal also reached 29.9 C on Sunday, also breaking a record.<\/p>\n
Why is it so warm? Experts point\u00a0to a massive heat wave in the northern Pacific Ocean as one of the likely\u00a0culprits.<\/p>\n
The unusually warm ocean temperatures are pushing the jet stream north, says\u00a0University of British Columbia atmospheric scientist\u00a0Lualawi Mareshet Admasu.\u00a0<\/p>\n
The jet stream is a narrow band air that\u00a0flows quickly\u00a0west-east\u00a0over the Northern Hemisphere, acting as a boundary between colder air in the north and warm air in the south. Scientists are still figuring out the complex link between ocean heat waves and the jet stream, but Mareshet Admasu says\u00a0parts of Canada have felt “very warm air from southern or Equatorial regions”\u00a0as it shifts north.<\/p>\n
A large and unusually warm area of water in the northern Pacific Ocean on Monday is shown in this graphic from Environment and Climate Change Canada. (Environment and Climate Change Canda)<\/p>\n
“Some temperature records were broken by over five\u00a0degrees,” said Geoff Coulson, a warning preparedness meteorologist at Environment and Climate Change Canada.<\/p>\n
“That is a very rare occurrence,” he said, as records are typically broken by “a fraction of a degree, or maybe a degree or two at most.”<\/p>\n
WATCH | Montrealers react to unsual warm fall weather\u00a0![\"\"](\"https:\/\/www.newsbeep.com\/ca\/wp-content\/uploads\/2025\/10\/1759812008_231_default.jpg\")
<\/p>\n
How is it this hot? Mid-summer weather in October surprises Montrealers<\/p>\n
With a temperature record for this time of year broken, many took advantage of what feels like an extended summer \u2014 although not everyone was so warm on the weather. <\/p>\n
The current marine heat wave is similar to the so-called “blob<\/a>,” a multi-year band of warm water that\u00a0significantly affected\u00a0marine life and fisheries off the U.S. and Canadian west coasts from 2013.<\/p>\n Studies have shown that marine heat waves are being made worse and more frequent by global warming, says William Cheung, director of the Institute for the Oceans and Fisheries at the University of British Columbia.\u00a0Since the “blob” there have been marine heat waves every year since 2019.<\/p>\n That means “we would be seeing more frequent and more intense heat waves happening as we move forward, if we don’t do a good job of mitigating climate change,” he said.<\/p>\n The ocean absorbs<\/a>\u00a0about 90 per cent of the atmosphere’s excess heat, which continues to warm because of greenhouse gas emissions from the burning of fossil fuels.\u00a0Temperatures in the northern Pacific this year are nearly 2.5 degrees warmer than the pre-industrial average, which is likely not a short-term fluctuation, according to an analysis<\/a> from the scientific group Berkeley Earth.<\/p>\n Previous marine heat waves had devastating impacts on local fisheries. The Pacific cod fishery off the coast of Alaska had to be closed<\/a> in 2020 due to low numbers. The entire Bering snow crab fishery \u2014 worth over $200 million US per year \u2014 collapsed<\/a> abruptly in 2018-19 after its numbers fell 90 per cent.<\/p>\n “Many people are dependent on the ocean directly for food, for culture, for livelihood,” Cheung said.<\/p>\n “At the same time, through the changes in weather systems [the marine heat] affects, it also affects people in a more indirect way.”<\/p>\n Meanwhile, on land, the forecast shows temperatures returning closer to seasonal normals this week as a cold front moves through Ontario and Quebec. But Admasu says researchers like him will be watching the Pacific heat wave, which is not letting up.<\/p>\n “The ocean changes at slower time scales than the atmosphere itself. So generally when you have these these impacts, they tend to stay or\u00a0persist for some time,” he said, adding\u00a0he expects a warmer than usual fall in North America overall.<\/p>\n","protected":false},"excerpt":{"rendered":"Many Canadians experienced decidedly un-fall-like weather last weekend, with temperatures soaring into the mid- to high-20s across many…\n","protected":false},"author":2,"featured_media":194512,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[2],"tags":[43,44,41,39,42,40],"class_list":{"0":"post-194511","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-headlines","8":"tag-headlines","9":"tag-news","10":"tag-top-news","11":"tag-top-stories","12":"tag-topnews","13":"tag-topstories"},"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/posts\/194511","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/comments?post=194511"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/posts\/194511\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/media\/194512"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/media?parent=194511"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/categories?post=194511"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/tags?post=194511"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}![\"A](\"https:\/\/www.newsbeep.com\/ca\/wp-content\/uploads\/2025\/10\/fea-wea-ottawa-heat-20250728.jpg\")
A dog wears tinted goggles while being walked along Dow’s Lake in Ottawa on July 28, when temperatures hit 33 C. (Sean Kilpatrick\/The Canadian Press)<\/p>\n