It looks like jet stream patterns are not moving very quickly across the northern realms of Earth at this time, compared to the past?
Your observation is well-supported by a growing body of recent science. Here's a thorough breakdown of what's happening with the jet stream over the Northern Hemisphere and why it matters — especially for someone in central Alberta.
The Jet Stream Is Slowing and Stalling
The polar jet stream — the fast-moving river of high-altitude wind that circles the Northern Hemisphere at roughly the latitude of Canada's southern border in winter — is indeed behaving differently than it did in past decades. The core mechanism is well established: the jet stream is powered by the temperature contrast between the cold Arctic and the warmer mid-latitudes. As the Arctic warms roughly three to four times faster than the global average (a phenomenon called Arctic amplification), that contrast weakens, and the jet stream loses its driving energy.[1][2][3]
The result is a slower, more sluggish wind current that tends to meander more wildly north and south rather than carrying weather systems briskly from west to east. Dr. Jennifer Francis of the Woodwell Climate Research Center describes it clearly: as jet-stream winds slow down, its waves grow bigger and extend farther north and south, and those larger waves move eastward more slowly — locking weather patterns over regions for days or weeks instead of days.[2][4][1]
The Arctic Is Feeding the Problem
The Arctic sea ice backdrop makes this worse right now. Arctic winter sea ice reached its lowest maximum extent in the 48-year satellite record in both 2025 and 2026, with 2026 reaching 14.29 million km² — statistically tied with 2025's record low. The 2026 maximum was roughly 1.36 million km² below the 1981–2010 average — an area twice the size of Texas. With less sea ice, the Arctic Ocean absorbs more solar radiation, further warming the polar region and further eroding the temperature gradient that drives jet stream speeds.[5][6][7]
Total Arctic sea ice volume in early 2026 was the lowest on record, even lower than 2025, and about 15% below mid-March 2024 levels. NOAA reported that between October 2024 and September 2025, Arctic temperatures reached their highest levels in 125 years of recorded observations. This is the exact feedback loop that atmospheric scientists have been tracking — less ice → more Arctic warmth → weaker jet stream.[8][9]
Stalled Waves: A Tripling of "Locked" Weather Events
The most alarming recent finding comes from a 2025 study published in PNAS by Michael Mann and colleagues, analyzing data from 1950 to 2024. It found that quasi-resonant amplification (QRA) events — episodes where large planetary waves in the jet stream become literally locked in place — have tripled in frequency since the 1950s. In the 1950s, Earth averaged about one such locked-wave summer event per year; now it averages about three, with some summers experiencing as many as six.[10][11]
These are the events behind some of the most destructive weather in recent memory:
- The deadly 2021 Pacific Northwest heat dome (and the Lytton, BC record of 49.6°C)
- The 2010 Russian heatwave and simultaneous Pakistan flooding
- The 2003 European heatwave
- The 2016 Fort McMurray wildfires in Alberta[11]
The mechanism: when the jet stream gets stuck in a deeply wavy configuration, ridges of high pressure lock in place producing heat domes, while troughs lock in place producing prolonged storms and floods. Canada, and Central Alberta in particular, sits squarely in the zone where these blocking patterns produce dramatic swings.[12][13][14]
An Active Scientific Debate
Not all scientists agree on the same interpretation. A 2020 University of Exeter study found no long-term increase in the actual waviness (amplitude) of the jet stream over the multi-decade record, arguing instead that observed links between Arctic warming and a wavier jet stream may reflect natural variability rather than a direct causal chain. Similarly, a June 2025 Dartmouth study using 125 years of ice-core-derived data found that pronounced wavy jet-stream phases have occurred naturally throughout the 20th century, before climate change was a significant factor, suggesting the current waviness isn't historically unprecedented.[15][16]
Most recently, a June 2026 study from Harvard SEAS published in Science Advances challenged the QRA mechanism itself, finding that in model tests, conditions theorized to produce large trapped waves actually produced smaller waves — calling for more caution in invoking QRA as the sole explanation for increasing extreme events.[17]
The scientific consensus, however, still points to a net slowdown in west-to-east progression of weather systems, greater persistence of blocking events, and more frequent stalling — even if the precise mechanisms are debated.[12][18]
What This Means for Alberta
For Central Alberta, these dynamics translate directly into experienced weather patterns:
- Omega block patterns (a high-pressure ridge bookended by two troughs) repeatedly set up over Canada, including late May and June 2026, producing prolonged heat and temperature extremes on the Prairies[19][20]
- When the jet stream dips south over the continent's centre, it delivers anomalous cold or storm systems well south of normal; when it arches north over the Prairies, heat domes and wildfire conditions build[14]
- Weather systems that used to traverse the continent in 3–5 days now frequently stall, extending heat, drought, or rainfall events by weeks[2]
The broader picture your observation captures is real and well-documented: the Northern Hemisphere's atmospheric "conveyor belt" has become less reliable, more erratic, and more prone to parking weather extremes over your region and others across the mid-latitudes.
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- https://arctic-council.org/news/shifting-winds-how-a-wavier-polar-jet-stream-causes-extreme-weather-events/
- https://theconversation.com/what-the-jet-stream-and-climate-change-had-to-do-with-the-hottest-summer-on-record-remember-all-those-heat-domes-238493
- https://climate.sustainability-directory.com/learn/how-does-the-jet-stream-relate-to-arctic-amplification/
- https://news.yale.edu/2022/09/12/meandering-waves-connect-jet-streams-global-warming
- https://www.carbonbrief.org/very-alarming-winter-sees-arctic-sea-ice-hit-record-low-for-second-year-running/
- https://science.nasa.gov/earth/arctic-winter-sea-ice-2026/
- https://iccinet.org/record-low-2026-arctic-sea-ice-maximum-why-its-essentially-a-tie-with-2025/
- https://iccinet.org/2026-arctic-sea-ice-maximum-among-lowest-on-record/
- https://www.theguardian.com/world/2025/dec/16/artic-record-heat-shrunken-sea-ice-report
- https://www.ajc.com/news/2025/06/study-finds-planetary-waves-linked-to-wild-summer-weather-have-tripled-since-1950/
- https://michaelmann.net/atmospheric-warming-and-planetary-wave-amplification/
- https://news.sustainability-directory.com/climate/stalled-jet-stream-events-tripled-since-1950-driving-extreme-summer-weather/
- https://www.cbc.ca/news/canada/edmonton/how-kinks-in-the-jet-stream-can-push-our-weather-to-extremes-1.6304014
- https://www.cbc.ca/news/canada/calgary/wacky-summer-weather-blame-the-jet-stream-climatologist-says-1.2725818
- https://www.sciencedaily.com/releases/2020/02/200219152855.htm
- https://home.dartmouth.edu/news/2025/06/study-winter-jet-stream-was-erratic-climate-change
- https://phys.org/news/2026-06-atmospheric-theory-falls-short-extreme.html
- https://www.ehn.org/new-research-links-stalled-jet-stream-to-rising-summer-weather-extremes
- https://www.theweathernetwork.com/en/news/weather/forecasts/this-blocking-pattern-may-deliver-canada-its-hottest-reading-of-2026
- https://www.youtube.com/watch?v=zH1wL5Kg6DU
- https://pmc.ncbi.nlm.nih.gov/articles/PMC4455715/
- https://www.meereisportal.de/en/news-overview/news-detail-view/mosaic-a-booster-shot-for-research-into-how-the-arctic-affects-our-weather
- https://www.nature.com/articles/s41612-025-01262-y
- https://www.pnas.org/doi/10.1073/pnas.2200890119
- https://www.met.reading.ac.uk/~williams/publications/3-s2.0-B9780128215753000153-main.pdf
- https://www.climatecentral.org/climate-matters/climate-change-the-jet-stream
- https://wcd.copernicus.org/articles/6/595/2025/
- https://www.space.com/science/climate-change/2025s-extreme-weather-had-the-jet-streams-fingerprints-all-over-it-from-flash-floods-to-hurricanes
- https://acp.copernicus.org/articles/22/4867/2022/
- https://www.facebook.com/groups/utah.weather.analysis/posts/27735976242694178/
- https://courses.seas.harvard.edu/climate/eli/Courses/global-change-debates/Sources/Jet-stream-waviness-and-cold-winters/3-Barnes-2013.pdf
- https://tellusjournal.org/articles/10.3402/tellusa.v68.32330
- https://www.youtube.com/watch?v=xR2PSGlFHaI
- https://www.nature.com/articles/s41586-019-1465-z
- https://www.nature.com/articles/s43247-025-03052-z
- https://en.wikipedia.org/wiki/Jet_stream
- https://www.carbonbrief.org/jet-stream-is-climate-change-causing-more-blocking-weather-events/
- https://www.nature.com/articles/s41467-018-05256-8
- https://www.science.org/doi/10.1126/science.aat0721
- https://phys.org/news/2026-05-arctic-winter-sea-ice-extent.html
- https://climate.copernicus.eu/sea-ice-cover-january-2026
- https://www.climate.gov/news-features/event-tracker/2025-winter-maximum-sea-ice-extent-arctic-smallest-record
- https://www.carbonbrief.org/arctic-sea-ice-winter-peak-in-2025-is-smallest-in-47-year-record/
- https://www.netweather.tv/charts-and-data/global-jetstream
- https://arctic.noaa.gov/report-card/report-card-2025/sea-ice-2025/
- https://pmc.ncbi.nlm.nih.gov/articles/PMC12552637/
- https://nsidc.org/sea-ice-today/analyses/arctic-sea-ice-sets-record-low-maximum-2025
- https://www.youtube.com/watch?v=UgXlnu7TwNM
- https://www.youtube.com/watch?v=Eo_HxQeCpW0
- https://michaelmann.net/wp-content/uploads/2025/06/LiEtAl_PNAS2025.pdf
- https://www.pnas.org/doi/10.1073/pnas.1412797111
- https://www.youtube.com/watch?v=pFsZdZeQHSo
- https://science.nasa.gov/earth/earth-observatory/unusual-july-temperatures-84150/
- https://www.theweathernetwork.com/en/news/weather/seasonal/atlantic-canada-new-brunswick-pei-nova-scotia-newfoundland-labrador-summer-forecast-2026?guid_iss=1
- https://www.facebook.com/MeteorologistEddieSheerr/posts/a-pattern-called-an-omega-block-has-set-up-across-north-america-named-because-th/1542547500562376/
- https://www.nature.com/articles/s41598-024-72787-0
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