"Very little cloud and clear skies across the majority of Spain, except for Galicia, Cantabria and the north of the Canary Islands which will experience some cloud," Spain's weather agency Aemet forecast for Tuesday.
Seville will experience highs of 38C on Tuesday, while Madrid will be 31C and Zaragoza 33C.
The coastal cities of Barcelona and Valencia will be cooler, at around 25C on Tuesday, according to Aemet.
Wednesday forecast for Spain.
On Wednesday, Aemet has issued a "significant weather phenomenon" of high temperatures in the Ebro Valley and across the south of mainland Spain, especially in the Guadalquivir Valley, which encompasses the cities of Seville and Cordoba, which will experience temperatures of 39C.
By Thursday, temperatures will have risen to 36C in Madrid and 40C in Cordoba.
Weather experts have predicted a hotter-than-average summer for Spain but thankfully, no heatwaves.
Spain experienced some of its highest ever temperatures in 2015, when the country sweated through three separate heatwaves.