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High latitude high pressure blocking forcing the polar vortex to split and shift south delivering frigid air to the middle latitudes occurs in Russia the next 7-10 days. However, the arctic oscillation flips positive days 11-14 as the polar vortex returns to home base in the polar region.

Discussion: Stratospheric warming is forecast across the northern hemisphere much of the next 2 weeks mostly focused on north/northeast Asia. Beneath the stratospheric warming is removal of the polar vortex from the polar region southward causing arctic cold outbreaks. The arctic air evolves over Russia the next week or so. As the arctic air develops beneath the displaced polar vortex a negative arctic oscillation develops. However, the Asia polar vortex shifts east over the North Pacific later this month weakening the polar vortex. Interestingly, the 8-10 day period of -AO reverses to the positive phase days 11-14 which supports a milder mid-latitude climate.