Dangerous ‘Omega block’ trapping scorching air over US & Canada
The Northwestern United States and Pacific Canada are in the grips of a heat wave that the National Weather Service called “historic and dangerous” in a bulletin on Sunday (June 27). A weather anomaly called a “heat dome” is partially to blame.
In the last few days, multiple cities across Washington, Oregon, Northern California and British Columbia have seen scorching all-time heat records fall, including a reading of 108 degrees Fahrenheit (42 degrees Celsius) in Seattle on Sunday (June 27) — the city’s highest recorded temperature ever — and a high of 117 F (47 C) in Salem, Oregon, on the same day. In Portland, the city’s streetcar system had to cancel service for the day because the power cables were melting in the heat.
Meanwhile, north of the Canadian border, the town of Lytton, British Columbia, recorded a high of 116 F (47 C) on Monday — the hottest temperature ever recorded anywhere in Canada, according to NASA’s Earth Observatory.
While average summer temperatures are steadily increasing every year due to human-induced global warming (2020 tied 2016 for the planet’s hottest year on record, Live Science previously reported), a meteorological anomaly is also partly to blame for the Pacific Northwest heat.
Conflating high- and low-pressure systems have trapped the region in a so-called heat dome, according to CBS News — essentially, “a mountain of warm air” locked in place by undulations in the jet stream (a river of strong wind weaving high through the upper atmosphere), the news site reported.
In this case, the jet stream has trapped a ridge of high pressure (that’s the heat dome) over the Pacific Northwest, creating a block in the atmosphere that prevents the weather system from moving on.
Instead, the hot air in the high-pressure system pushes down over the region, creating a suffocating blanket of heat. As you can see in weather maps like this one, the wind patterns swirl around the heat block in the shape of the Greek letter Omega — giving systems like these the nickname “Omega blocks,” according to CBS.
Fortunately, it seems that the worst is over for now, the National Weather Service reported on Tuesday (June 29), with “the stagnant upper-level high pressure in place over the region [beginning] to shift to the east over the next couple of days.”
The highest temperatures will likely fall in eastern Washington, Oregon and western Idaho for the next few days, the NWS added, and eventually move over Montana by Thursday (July 1). Excessive heat advisories remain in effect for much of the region.
See more here: livescience.com
Header image: NASA Earth Observatory
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RT
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Total uproar panic over natural weather. EOTW NOT. Not telling about the 50-60 degree drop on overnight. It is always amazing what they leave out. https://electroverse.net/accuweather-meteorologist-global-warming-not-to-blame-for-northwests-heatwave/ But must maintain the CC fallacy at all cost. Marxism rules.
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Jerry Krause
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Hi PSI Readers,
I read: “Temperatures over the period differ based upon the location on the Earth; regions near the equator are typically warmer than those lying near the poles. This is because, due to the curve of the Earth, these places receive the most sunlight, according to Atmospheric Radiation Measurement (ARM) Program.” (I copy statements like this and links and first paste them in ‘Apple’s Pages’ where I sometimes begin composing my comments.). Now as I come back to this article at PSI, I have no idea where I copied this quote. Which I consider something to be considered.
For, we should NOT ignore the fact when this ‘heat’ has occurred was just after the Summer Solstice when the longest daytimes of the year occur in the Northern Hemisphere and the shortest nighttimes of the year occur. And we know that the higher the latitude the longer the daytime and the shorter the nighttime until we reach the latitude, above which,, the sun no longer rises and there is continuous daytime.
It seems too often we might focus only on the incident angle of solar radiation and not upon the length of the daytime and nighttime periods. Especially the length of the nighttime periods
when there is no incident angle involved and the air temperature near the surface generally cools..
This comment is only to alert a PSI Reader of these facts which I have just reviewed before we begin to consider the also important Jet Stream (about which we have known of its existence for less than a century) as the primary factor which has caused this extreme, extreme heat. Which also should NOT be ignored.
In the figure of the (link to titled Omega Block there are little white arrows; what are these white arrows representing? And you refer to “a mountain of warm air”. When I study atmospheric sounding data (http://weather.uwyo.edu/upperair/sounding.html) and the data of the RAWS project (https://raws.dri.edu) I find that the extreme heat seems confined to the lower elevations (atmosphere) and I can see that the white arrows are being blocked by what in Oregon we refer to as the Coast Range. Hence, I consider the white arrows represent near surface winds.
Finally, one last comment. I find that our understanding of the Jet Streams is extremely limited. I believe, but don’t know, that many believe that a jet stream has no beginning and end; it just circles the globe of the Earth. However, I believe the one being pictured in the figure begins in the high mountains of Tibet and ends at some high latitude of North America.
And I understand that these comments give people a target to shot little arrow like comments at me.
Have a good day, Jerry
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Mark Tapley
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Hello Jerry:
The Davos “Green Energy” crowd will always jump on any item they can use to prop up their climate change narrative. Just a few years ago New England had record cold temperatures and it snowed in Cairo Egypt for the first time in 118 years. I guess that was “global warming.” The MSM present their biased narrative only to cultivate their pre planned Zionist agenda. The weather is no exception. The truth is often more like Will Rogers quipped: “If you don’t like the weather in Oklahoma, wait a minute and it’ll change.”
Scientists say we are now entering a moderate cooling phase due to less solar activity. This is unfortunate because overall, plant growth is boosted by more heat. The medieval warming cycle was a great benefit to agriculture and also the general economy. Also excessive cold kills more people than the heat.
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Greg Alberta
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Nothing to do with the Grand Solar Minimum, historically low solar activity, cloud-nucleating Cosmic Rays, and a meridional jet stream flow? This was predicted 5 years ago. Where have you people been and what propaganda have you been reading? Not Valentina Zharkova’s research it seems.
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Laura
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GEOENGINEERING. The evidence is overwhelming and much is from government documents.
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Tom
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Good grief! Pass the pizza Teresa, no I mean pass the ice cubes…the earth is melting 9 years ahead of schedule. Can’t those darn global warming freaks get anything right? In my neck of the woods, over the last 5-10 years, the temps have been lower, even in summer and the storms have been much weaker and fewer. I can’t even experience a good old 1960’s style thunderstorm with 30 minutes of lightening, deep thunder boomers, steady rain and high winds. Even the cat isn’t scared of these wimpy storms anymore.
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Protestant
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HAARP? “In mid-August 2015 control of the facility and its equipment was turned over to the University of Alaska Fairbanks, which is making the facilities available for researchers on a pay-per-use basis.”
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