Officials reported 1,149 excess deaths in Spain from August 3rd to 18th, according to AFP.
The Institute used data from the Spanish Mortality Monitoring System (MOMO) compared to historical trends.
External factors, such as weather data from the National Weather Agency AEMET, have also been incorporated to assess possible causes of mortality spikes.
Although MOMO cannot confirm the direct cause between death and high temperatures, it provides the most reliable estimate of deaths where fever is likely to be the critical factor.
In July, the Carlos III Institute rose 57% in the same period last year due to severe heat, due to 1,060 excess deaths.
Climate experts say global warming is driving longer, more intense, and more frequent heat waves around the world.
MNA