OVIEDO, Spain

Spain's meteorological service issued its first heat advisory of the year for Andalusia on Thursday, as an African air mass brings mid-summer temperatures to large parts of the country.

Temperatures soared to around 38 degrees Celsius (100 Fahrenheit) in Cordoba, where health authorities advised people to stay indoors during the hottest hours of the day.

The mercury has been climbing all week, with Wednesday seeing several major cities broke records for the hottest day ever recorded in April.

Toledo, Huelva, Jaen, Cordoba, Granada, Seville, and Teruel all surpassed previous maximum temperature records for April on Wednesday, and many are expected to break them again on Thursday.

Current temperatures are typical of July and more than 15C (59F) hotter than the seasonal average, according to Aemet, Spain's meteorological agency.

On Thursday, the Spanish Health Ministry proposed moving its national heat protocol to mid-May instead of June, as the country continues to face exceptionally hot, dry weather.

The latest bout of heat exacerbates the country's ongoing drought, which is severely impacting several key agricultural crops. As of Tuesday, Spain's water reserves were only half full – 17 percentage points below the 10-year average for this time of year.

Meanwhile, the risk of fires has risen to "extreme" levels in approximately half of Spain. With the heat expected to persist on Friday, fire risk levels are set to expand.

Spain has already experienced an unusually active wildfire season this spring.