"As I mentioned in last week’s blog, as long as high latitude blocking remains certainly focused near Scandinavia and the Barents-Kara Seas and even if it is more spread out between Greenland to the Barents-Kara Seas, the risk for a stretched PV remains high. This thinking is founded on our analysis of the tropospheric precursors to a stretched PV in Cohen et al. 2021.
However, if the high latitude becomes focused near Greenland that may bring some temporary colder weather to Europe and even the Eastern US but that does not seem favorable to me to weaken the PV especially if low pressure develops near the Urals at the same time. The exception would be if the high latitude blocking quickly slides east towards the Barents-Kara Seas also based on Cohen et al. 2021. This of course assumes that there is also high latitude blocking in the northern North Pacific sector between eastern Siberia and Alaska. This generalized wave-two pattern of high pressure ridging in the North Atlantic sector of the Arctic and the North Pacific sector of the Arctic with low pressure troughing across Asia and North America and into the North Atlantic seems very favorable for PV stretching. "
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