Ambient temperature, be it hot or cold, has an effect on aircraft operations irrespective of the airport elevation. Whilst the combination of heat and high altitude, as discussed in the SKYbrary article Hot and High Operations, has a particularly detrimental impact on aviation, heat alone can also have substantial repercussions when considering safe and efficient aircraft operations. Extreme heat, common to many areas in Africa and the Middle East, is becoming increasingly more common, albeit for relatively short periods of time, in other areas of the world, including Europe, Australia and North America.
A380 operating in high ambient temperature [source: wikicommons, author: Bill Abbott, July 2016]