If there is any field in which what was said by the famous physicist Niels Bohr that “it is difficult to make predictions, especially of the future“That is meteorology. Although it is not always the case.
There are times that, with all the uncertainties we want, “we see them come long before normal.” And that is what just happened: the main prediction models in the world They say we are going to a negative nao stage.
Something that, in the face of spring, can be excellent news.
What is NAO? ‘Nao’ are the acronym in English of ‘North Atlantic oscillation‘And basically refers to the’ dance ‘between the Azores anticyclone and the loss of Iceland, the two great atmospheric phenomena that govern the meteorology of the North Atlantic.
When the index we use to “measure who is winning” is negative, the anticyclone of the Azores is weaker than normal and, therefore, cannot block the deep storms of the Atlantic. The direct consequence is that, they circulate further than normal: in our latitudes.
Kristian Strommen et als. (2021)
The news is that, indeed, it seems that we are going to Noa negative. Both the NOAA American and the European ECMWF They coincide in which “we are at the gates of a Nao phase in descent.”
And what consequences would this have? The combination of a negative nao and a large mass of stagnant polar air in the continent would cause the circulation of deep storms to pass us over and, therefore, the weather conditions are stirred.
A summary of the situation. In the short term, we are in the midst of that cyclogenesis festival that we have already talked about, but when the stability will be installed again. That means that nocturnal temperatures will lower, the frost will return and the fog will return.
From then on, if the NOA phase change is confirmed, the situation becomes difficult to predict. The good part of this type of diagnoses is that it is very solid (that is, it is quite likely to pass); The bad is that the details become more complex: it can be triggered from a sudden stratospheric warming that froze everything that caught its path to almost nothing.
It is reasonable to wait for rain in one way (deep storms) or another (retrograde danas), however the prognosis is in the air.
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