500-mb pressure chart, valid 28 June 2021, 7:00 EST (11:00 UTC). The high pressure area centered over southern British Columbia is the cause of the heat dome, which led to the Pacific Northwest heat wave. Cropped for convenience. Geopotential height chart at 500 millibars at 11:00 UTC on June 28, 2021. The center of the heat dome, which caused the heat wave, can be seen over the British Columbia Interior. The heat dome of the 2021 Western North America heat wave, over west Canada and the Northwest United States. The "high" pressure at left is the heat dome.
<a href="https://en.wikipedia.org/wiki/en:National_Oceanic_and_Atmospheric_Administration" class="extiw" title="w:en:National Oceanic and Atmospheric Administration"><span title="agency in the United States Federal Government">National Oceanic and Atmospheric Administration</span></a>
2022-08-14
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