May and June: two unusually warm months in a row

BarcelonaThe month of June is over, and although in recent days the heat has become somewhat more bearable, in some places it will be the hottest month since records began. This is the case of Lleida, where the average for this month will be 26.6 °C, the highest at least since 1960, 0.4 ºC higher than the previous record, set in 2003. In Tortosa and in the airports of Girona and Reus the average temperature of 2003 and 2022 are almost the same, but the drop in temperature in recent days has meant it stayed below the previous record. In Barcelona's Fabra Observatory, this June will be the second warmest since records began, with an average temperature almost 1 ºC lower than in 2003.

In Catalonia as a whole, this June the average temperature was 21.7 °C, 3 degrees above the reference for the period 2009-2020, but the 30-day period between May 15 and June 15 the anomaly reached 4.2 degrees, an extraordinary figure for an average temperature for Catalonia as a whole and calculated for a period of one month. It is like saying that for 30 days in a row every day in Catalonia there were more than 4 degrees more than there should be. We must remember that if we compare this year's data with previous periods, the anomaly would be even stronger. It was clearly the hottest June at least since 2009, and the data of some individual records suggests that in Catalonia as a whole, if it was not higher than in 2003, it will have been very close.

We must take into account that the month of May had already broken records in many observatories, which means that we are on track for the longest summer ever experienced. In Catalonia, with data from 87 observatories, this year until June 30 there have already been 1,530 temperatures over 30 degrees. Each temperature over 30 degrees represents a day and an observatory where this threshold has been reached. This is certainly the highest since at least 2009 and probably since records began, since, although open Meteocat data we use to make these calculations do not go back beyond 2009, comparisons with longer records make it clear May and June registering such astonishingly high temperatures are highly unlikely to have occurred since records began.

Some of the conclusions that can be drawn from this calculation are truly staggering: on average in the 2009-2020 period, this amount of summer temperatures has been reached in the first days of August.

Some recent years have had a total of 30+ degree temperatures in all stations by the end of the year which was very similar to what we have already had in the first half of this year. In 2014 there were 1,538 in the whole year, about the same as this year on July 1, with 15 days of the heat wave still to go. The summer of 2014 was undoubtedly cool, but other recent data is quite similar, such as 2011, when there were just over 1,600, and 2010 was just over 1,750.

To make things worse, we are now heading into a new episode of really strong heat that will bring the thermometer back to near 40 °C over the next few days. Between Sunday and Tuesday the temperature will be very high again, and although nothing suggests that the mid-June data will be exceeded, we must expect temperatures close to 40 ° C inland in Catalonia and felt air temperatures of 35 °C on the coast.