Global Information2021 Western North America heat wave information
 Air temperature anomalies across North America on June 27, 2021, compared to 2014–2020 baseline | |
| Type | Heat wave |
|---|---|
| Start date | June 25, 2021 |
| End date | July 7, 2021 |
| Peak temp. | 49.6 °C (121.3 °F), recorded at Lytton, British Columbia[1] |
| Losses | |
| Deaths | 1,400 deaths (estimated),[2][3] 914 (confirmed)
|
| Damages | United States: ≥$8.9 billion (2021 USD)[4] |
The 2021 Western North America heat wave was an extreme heat wave that affected much of Western North America from late June through mid-July 2021.[5] The heat wave affected Northern California, Idaho, Western Nevada, Oregon, and Washington in the United States, as well as British Columbia, and in its latter phase, Alberta, Manitoba, the Northwest Territories, Saskatchewan, and Yukon, all in Canada.[6] It also affected inland regions of Central and Southern California,[7] Nevada, and Montana, though the temperature anomalies were not as extreme as in the regions farther north.
The heat wave appeared due to an exceptionally strong ridge centered over the area, whose probability of formation was linked to the effects of climate change by multiple studies.[8][9] It resulted in some of the highest temperatures ever recorded in the region,[10] including the highest temperature ever measured in Canada at 49.6 °C (121.3 °F), as well as the highest temperatures in British Columbia, in the Northwest Territories, in the state of Washington as well as a tied record in Oregon. The record-high temperatures associated with the heat wave stretched from Oregon to northern Manitoba, and daily highs were set as far east as Labrador and as far southwest as Southern California.
The extreme heat sparked numerous, extensive wildfires, some reaching hundreds of square kilometers in area. The eponymous Lytton wildfire destroyed the village of Lytton, British Columbia, the day after the city set the record high temperature for Canada. Extreme heat also damaged road and rail infrastructure, forced closures of businesses, disrupted cultural events, and melted snowcaps, in some cases resulting in flooding.[11] The heat wave also caused extensive damage to agriculture across the region, resulting in substantial loss of crop yield and the death of 651,000 farm animals.[12] The National Oceanic and Atmospheric Administration (NOAA) estimated that the heatwave caused at least $8.9 billion (2021 USD) in damages in the USA.[4]
The death toll exceeded 1,400 people, with at least 808 estimated in western Canada.[2] The Chief Coroner of British Columbia reported that 619 deaths were recorded due to heat exposure in the week from June 25 to July 1.[13] Confirmed deaths in the United States include at least 116 in Oregon (of which 72 are in Multnomah County, which includes Portland),[14] at least 112 in Washington[15] and one death in Idaho;[16] An analysis by The New York Times suggests that around 600 excess deaths occurred the week the heat wave passed through Washington and Oregon.[3]
- ^ Cite error: The named reference
:29was invoked but never defined (see the help page). - ^ a b Global Catastrophe Recap September 2021 (PDF) (Report). Aon Benfield. October 12, 2021. p. 13. Archived (PDF) from the original on October 18, 2021. Retrieved October 12, 2021.
- ^ a b Popovich, Nadja; Choi-Schagrin, Winston (August 11, 2021). "Hidden Toll of the Northwest Heat Wave: Hundreds of Extra Deaths". The New York Times. ISSN 0362-4331. Archived from the original on January 1, 2022. Retrieved August 11, 2021.
- ^ a b "Billion-Dollar Weather and Climate Disasters: Events". NOAA. February 2022. Archived from the original on December 25, 2012. Retrieved February 11, 2022.
- ^ Cite error: The named reference
:48was invoked but never defined (see the help page). - ^ Dickson, Courtney (June 25, 2021). "Western Canada heat wave expected to break daily, all-time temperature records". Canadian Broadcasting Corporation. Archived from the original on June 26, 2021. Retrieved June 26, 2021.
- ^ Seidman, Lila (June 25, 2021). "Scorching weekend ahead prompts heat warnings in Southern California". Los Angeles Times. Archived from the original on June 28, 2021. Retrieved June 29, 2021.
- ^ "Rapid attribution analysis of the extraordinary heatwave on the Pacific Coast of the US and Canada June 2021" (PDF). World Weather Attribution. Archived (PDF) from the original on July 7, 2021. Retrieved August 17, 2021.
- ^ Bartusek, S.; Kornhuber, K.; Ting, M. (2022). "2021 North American heatwave amplified by climate change-driven nonlinear interactions". Nature Climate Change. 12 (12): 1143–1150. Bibcode:2022NatCC..12.1143B. doi:10.1038/s41558-022-01520-4. S2CID 254000529. Archived from the original on June 9, 2023. Retrieved June 9, 2023.
- ^ Berardelli, Jeff (June 27, 2021). "Pacific Northwest bakes under once in a millennium heat dome". CBS News. Archived from the original on June 27, 2021. Retrieved June 27, 2021.
- ^ "Car submerged, road flooded as record-breaking B.C. heat prompts massive snow melt". Global News. July 11, 2021. Archived from the original on July 11, 2021. Retrieved July 21, 2021.
- ^ White, Rachel H.; Anderson, Sam; Booth, James F.; Braich, Ginni; Draeger, Christina; Fei, Cuiyi; Harley, Christopher D. G.; Henderson, Sarah B.; Jakob, Matthias; Lau, Carie-Ann; Mareshet Admasu, Lualawi; Narinesingh, Veeshan; Rodell, Christopher; Roocroft, Eliott; Weinberger, Kate R. (February 9, 2023). "The unprecedented Pacific Northwest heatwave of June 2021". Nature Communications. 14 (1): 727. doi:10.1038/s41467-023-36289-3. ISSN 2041-1723. PMC 9910268. PMID 36759624.
- ^ Michael Egilson; Kristy Anderson; Jatinder Baidwan; Alex Boston; Sam Bugis; Rowan Burdge; Gerry Delorme; Michael Christian; Ken Craig; Kirsten Everett; Reka Gustafson; Sarah Henderson; Christina Krause; Shannon McDonald; Kim McGrail; Isobel Mackenzie; Jim Ogloff; Norm Peters; Michael Schwandt; Daniel Stevens; Magdalena Szpala; Fiona Wilson; Amina Yasin (June 7, 2022). "Extreme Heat Death Review Panel Report - extreme_heat_death_review_panel_report.pdf" (PDF). Province of British Columbia. Archived (PDF) from the original on July 27, 2022. Retrieved July 26, 2022.
- ^ Tabrizian, Ardeshir (July 7, 2021). "Oregon's heat wave death toll grows to 116". The Oregonian. Archived from the original on July 8, 2021. Retrieved July 8, 2021.
- ^ Ryan, John (July 20, 2021). "2021 heat wave is now the deadliest weather-related event in Washington history". KUOW. Archived from the original on July 20, 2021. Retrieved July 22, 2021.
- ^ Schwedelson, Paul (July 8, 2021). "Treasure Valley has first death caused by heat wave". Idaho Press. Archived from the original on July 8, 2021. Retrieved July 8, 2021.