Heat wave

An episode of abnormally high temperatures that persists for several days and affects a large geographical area. In Spain, the Spanish Meteorological Agency (AEMET) defines a heat wave as lasting at least three consecutive days in which all of the meteorological stations considered record abnormally high temperatures (maximums above the 95th percentile of the daily maximum temperature series for July and August during the period 1971-2000). The longest heat wave recorded in Spain was in 2015, lasting twenty-six days, while the summer of 2017 saw the most heat waves (five).