The summer of San Miguel extends August until the weekend throughout Spain and will leave maximums of 38ºC

• The Weather When is the summer of San Miguel this 2023 and where does the expression come from?

September will give way to October with the closure of a 'summer of San Miguel' that could be "the hottest" in the last 30 years, with maximum temperatures that will continue to rise progressively until the weekend, when the thermometers will be between 10 and 15 degrees above normal, according to the State Meteorological Agency (AEMET) that warns that in the Guadalquivir valley will reach 38ºC.

It is, according to the spokesman, Rubén del Campo, an episode of high temperatures that will be accompanied by the absence of rainfall in most of Spain.

Specifically, it points out that the warmest days of this episode will be from Friday to Monday, when the maximum will be between 36ºC to 38ºC in the Guadalquivir Valley and will be between 32ºC to 34ºC in numerous areas of the peninsular interior in addition to the Canary Islands, with oscillations of 34ºC to 36ºC from the weekend in the eastern islands.

Although the AEMET expects this heat episode to end in the middle of the first week of October but warns that this 'summer of San Miguel' will be extensive and intense.

Del Campo explains that this hot episode is due to atmospheric stability under high pressures, which favors clear skies, so the sun shines brightly and warms the surface a lot. In addition, he adds that the weak winds push away the mixture of air, which is compressed and heated by the descents it makes from high to low levels of the troposphere within those high pressures.

All this will take place under a mass of air from subtropical latitudes that will also be extraordinarily warm for the time of year, a phenomenon that, according to data from the AEMET, will be "the warmest compared to those that have occurred between 1991 and 2020".

On the other hand, since the summer began, temperatures have been high for the time of year, since on Tuesday several towns in theGuadalquivir and Guadiana Valleys touched 34ºC, such as Andújar, Jaén, Córdoba or Badajoz, while in much of the peninsular interior the daytime maximums were between 4ºC and 7ºC above usual.

Also, temperatures will rise significantly this Wednesday in the Cantabrian Cornice, although it will be less pronounced in other parts of the northern half. Meanwhile, temperatures will already exceed 30ºC in the Eastern Cantabrian, the Ebro depression and the central area of Castilla y León as well as in much of the center and south of the peninsula, while in points of the Guadalquivir they will reach 34ºC.

These values represent an increase of between 5ºC and 10ºC above normal in much of the territory, a trend that will continue on Thursday when temperatures will also rise slightly in the southern half of the peninsula although unchanged in the rest of the country according to the spokesman.

FIRE RISK IN THE CANTABRIAN SEA

However, although the skies will be little cloudy in general, the spokesman has pointed out that it could rain weakly in the far east of Galicia. Despite this, del Campo has insisted that on Thursday more than 30ºC will be registered in the Cantabrian Sea, where the risk of fires will also be very high.

Likewise, the northeast, center and south of the peninsula will also exceed 30ºC, while in much of southern Extremadura, Castilla-La Mancha and Andalusia the values will oscillate between 32ºC and 34ºC

As for Friday, it indicates that temperatures will rise "considerably", since the maximum for this period between 36ºC and 38ºC, so in cities of the Guadiana and Guadalquivir Valleys, such as Badajoz, Córdoba and Seville, temperatures will be "more typical of the second half of August, in the middle of summer".

In the rest of the Peninsula will exceed 30ºC in a generalized way, which will continue on Saturday mainly in the central hours of the day, in addition to there will be an increase in minimum temperatures, since it will not fall between 18ºC and 20ºC on the Mediterranean coast and areas of Andalusia and Extremadura.

The values will be higher than 32ºC in many areas of the interior of the Cantabrian communities (where the risk of fires will continue to be activated) as well as in several points of Castilla y León and the peninsular center.

With respect to the surroundings of the Ebro, temperatures will touch 34ºC, a value that will be exceeded in Extremadura, western Castilla-La Mancha and Andalusia, while the Guadiana and Guadalquivir Valleys will register again around 36ºC and38ºC on Saturday.

TEMPERATURE RECORDS In October

According to the spokesman, on Sunday a notable drop in temperatures is expected on the Cantabrian coast, although they will increase in the east of the peninsula and the Balearic Islands, and while they will remain without major changes in the rest. In this way, the first week of October will still register values of 36ºC to 38ºC in areas of the Guadiana and the Guadalquivir.

With all this, from September 28 to October 4 could break several records of warm days, since according to the spokesman, each of these days could be the hottest for that same date since at least 1950.

According to the National Climatological Data Bank of the AEMET, the maximum temperature recorded in the Peninsula in October was 37.5ºC in Marbella (Málaga) in 2014, followed by 37.4ºC in Andújar (Jaén) in 2004. Given the forecasts for the coming days, the spokesman does not rule out that these record temperatures could be exceeded.

On the other hand, this hot episode will persist at the beginning of next week, foreseeably until Wednesday, when a thermal decrease is expected that is still to be confirmed, according to the spokesman.

Finally, in the Canary archipelago there will be trade winds with clouds in the north of the islands of greater relief during this Wednesday and Thursday, while from Friday a thermal ascent will also begin that will leave higher temperatures for the season from Saturday until the first half of next week.

There it will be possible to exceed 34ºC in the south of the island of Gran Canaria, Lanzarote and Fuerteventura and, on the other hand, the spokesman has underlined the possibility of calima in the skies of the Canary Islands.