The polar vortex, the aftermath of global warming continues, and here «3B Meteo

The global warming event that occurred during the latter part of March caused a noticeable change in circulation in the past few days. Temperatures at the beginning of April were well below average in many countries of Central and Northern Europe but especially between Spain, France, Germany, the Alpine region, Poland and the Baltic states. The sub-thermal average also relates to Italy and the Northern Balkans. So many records were broken for April that for countries outside the Alps, it was an exceptional cold snap. The rain also returned to Italy But this still does not solve the problem of dehydration. On the other hand, as in the game of mirrors, warm subtropical air rose from North Africa towards the Middle East all the way to the heart of South Asia with peaks even more than 40/43°C. In fact, the temperature differences in early April correspond to post-stratospheric influenza events of a “hot” nature.

The major stratigraphic warming, which numerical models rarely predict, will coincide this year with the final warming, or the recent seasonal warming of the polar stratosphere; It also sharply reduced the region’s velocities to 10 hPa after winter marked a stronger-than-normal stratospheric polar vortex.

The effects of class warming are not yet over; The “drip” of the stratospheric signal is expected to continue in the next few days and will continue to affect the time of mid-latitudes. In particular, the greatest impact is expected to occur in North America where formation of an Alaskan anti-vortex outcrop, supported by La Nina, within the pronounced Rossby wave, will produce a pronounced change in circulation during Holy Week. Winter will still dominate western Canada and the United States while warm air from the Gulf of Mexico will reach the eastern states, from Georgia to New York. The large temperature difference will lead to a phase of bad weather in the Midwest with the potential for violent thunderstorms.

As it spreads eastward, the energy within the Rossby wave will strengthen the anti-eddy outcrop over Western Europe where temperatures will return to milder values ​​while at the same time the depression will isolate itself over the Mediterranean. There is still uncertainty about its development.

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