It does seem that the late surge at the end of the month helped to push the final SCE value into positive territory but not by much. I tend to underestimate the total value and hopefully the official value will be published later this week. In Figure i, I present the Eurasian snow cover extent (SCE) from 1979 to 2023 with 2023 being my estimate. Now that we have turned the page on October and now in early November, I will start to share how I interpret the snow cover advance across Eurasia in October. The driving from the troposphere is looking to be short-circuited this week and though it is still likely to happen, it looks like an unimpressive event. In the meantime, I have been expecting a stretching of the polar vortex like a rubber band being pulled on both ends to bring colder and snowier weather to Asia and North America in the second half of November. It is more than the last three years but not by much and I don’t consider it a definitive predictor of this winter but is biased to a colder winter. I am close to having the final number (see Figure i). I use October Eurasian snow cover extent as one of our main winter predictors. I continue the transition to the winter season, which should occur over the next few weeks.And I discuss the upcoming prospects of polar vortex behavior over the coming weeks. in the Impacts section I try to wrap up on October Eurasian snow cover as I believe October is the critical month for predicting the upcoming winter circulation and weather.This pattern generally favors normal to above normal temperatures across Alaska, much of Canada and the United States (US) with normal to below normal temperatures limited to the west coast of North America, far Eastern Canada and New England. The general predicted pattern across North America the next two weeks is troughing/negative geopotential height anomalies in the Gulf of Alaska forcing ridging/positive geopotential height anomalies across much of North America with downstream troughing/negative geopotential height anomalies across the Canadian Maritimes.This pattern favors normal to above normal temperatures across much of Asia including Northern Siberia with normal to below normal temperatures limited to East Aisa and then next week normal to above normal temperatures across Southern and Western Asia with normal to below temperatures becoming more widespread across Siberia. Then next week ridging/positive geopotential height anomalies will slide west and consolidate in Western Asia centered on the Urals while troughing/negative geopotential height anomalies will deepen in Siberia. This week the predicted pattern across Asia is ridging/positive geopotential height anomalies across Central Asia including Siberia with troughing/negative geopotential height anomalies across Eastern Asia.This mostly zonal pattern will support normal to above normal temperatures across much of Europe including the United Kingdom (UK) with normal to below normal temperatures mostly limited to Scandinavia the next two weeks. Over the next two weeks, the predicted general pattern across Europe is troughing/negative geopotential height anomalies across Northern Europe and ridging/positive geopotential height anomalies across Southern Europe.The North Atlantic Oscillation (NAO) is currently near neutral with mixed pressure/geopotential height anomalies across Greenland and the NAO is predicted to remain near neutral the next two weeks as pressure/geopotential height anomalies remain mostly mixed across Greenland. The Arctic Oscillation (AO) is currently positive and is predicted to remain near neutral the next two weeks as pressure/geopotential height anomalies across the Arctic are currently mixed and are predicted to remain mixed over the next two weeks.The AO/PV blog is partially supported by NSF grant AGS: 1657748. Subscribe to our email list or follow me on Twitter for notification of updates. Also, there will be less emphasis on ice and snow boundary conditions and their influence on hemispheric weather Snow accumulation forecasts will be replaced by precipitation forecasts. In late Spring, we transition to a spring/summer schedule, which is once every two weeks. Also, there is renewed emphasis on ice and snow boundary conditions and their influence on hemispheric weather. Snow accumulation forecasts replace precipitation forecasts. This analysis is intended to provide researchers and practitioners real-time insights on one of North America’s and Europe’s leading drivers for extreme and persistent temperature patterns.ĭuring the winter schedule the blog is updated once every week. Judah Cohen from Atmospheric and Environmental Research (AER) embarked on an experimental process of regular research, review, and analysis of the Arctic Oscillation (AO) and Polar Vortex (PV).
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