Analysis of July 2022 persistent and extreme high temperatures episode in the Basque Country

In this work we analyse one of the most intense heat episodes ever happened in the Basque Country. This historic event produces numerous absolute record. with the highest maximum and minimum temperatures, as well as the highest maximum and minimum values for a month of July. In addition, numerous fires are produced during this period. A red alarm for extreme high temperatures has been set for the first time (note that colour-coded warnings have been implemented in Euskalmet case in 2009).

The worst is between the 16th and 18th, although the period of high temperatures lasts from the 11th to the 18th. From the 16th to the 18th many stations exceed 40ºC. On the 16th, the highest temperatures are recorded in the south part, specifically at the Zambrana station with 41.7 ºC. On the 17th the intense heat is repeated, with temperatures rising in several areas, especially in the Cantabrian area of Alava. During this day, values above 42 ºC are recorded at several stations and above 40 ºC at a large number of them. Gardea and Saratxo reach 42.9 ºC and Ordunte 42.4 ºC respectively. The maximum temperatures are above 40 ºC in many stations in Alava, including Abetxuko in Vitoria (40.1 ºC). The 18th is another day of suffocating heat. With a prevailing southerly wind, temperatures rise on the Cantabrian slope, especially in Gipuzkoa, and 11 stations reach or exceed 42 ºC. In Gardea, 43.6 ºC is recorded, the highest temperature value recorded during the whole episode. In Arrasate and Saratxo the temperatures are also around 43 ºC, with 42.9 ºC and 42.7 ºC respectively.

Due to the heat, there are numerous incidents. One person dies of heatstroke. According to the Basque Government, health services treat a total of 184 people for conditions related to the high temperatures, 83 of whom are taken to hospital.

In this work, the synoptic and mesoscale factors of this episode are analysed. The information from Basque Country Automatic Weather Station Mesonetwork is reviewed, analysing the spatial-temporal evolution of the temperatures at different locations. Finally we include some conclusions taking into account other previous persistent and extreme temperatures episodes and some impact information.