The summer of San Miguel is here. The only problem is that the summer of San Miguel neither exists nor has it ever existed

We are at that time of the year in which Spain lives A curious phenomenon. Without prior notice, for no apparent reason: the thermometers shoot up to temperatures much warmer than normal for that time of the year. This 2025, According to Aemetwill also have its “temperature rebound” around the end of the month.

That is, he will have his ‘summer of San Miguel’.

What exactly is the ‘Summer of San Miguel’? What we know as Veranillo de San Miguel or Membrillo is a period of good weather and higher temperatures than usual that usually occurs at the end of September and early October. This is called for the festival of San Miguel, on September 29.

But the most interesting thing is that none of this exists.

What does not exist? Let’s go in parts: it is usually said that the Veranillo de San Miguel has no explanation, but the truth is that it is not true. Or, at least, it is not accurate.

We know perfectly why The “summers” have occurred of the last 30 years: for two or three days temperatures rise to simply lower because September is so. The days are long enough so that, as soon as there is some stability, temperatures rise, rise and rise.

In fact, they don’t even need to go up a lot. It is enough that they are only slightly superior to the previous days, so that we will talk about the “Veranillo de San Miguel” as if it were one more station.

A huge confirmation bias made popular meteorology. As we said a couple of years agowe have a strong tendency to “favor, search, interpret and remember the information that confirms your own beliefs” and that translates into that, when two days of higher temperatures of the average for this time of the year arise, let’s see a “summer” potential.

That is, in a phenomenon with a high probability (two or three days of good time at the end of September) we see a clear regularity – reinforced by the popular idea. Although the dates and temperatures do not always match, of course, a lot of those we have in summer are far from.

But will there be “summer”? Yes, there will be: just before Gabrielle impact with the west of the peninsulathe country will enjoy a warm and stable atmosphere.

And then? That summer is finally ended and these days will be his last bedroom. If traditionally ‘autumn’ is synonymous with ‘instability’ having a hurricane in the middle of the extroat transition to a week of us is to enter the fall through the big door.

Image | ECMWF

In Xataka | The “illusion of frequency”: why you see more sneakers after talking about shoes