When the heat is intense, delay the prayer until it becomes fairly cool, for intense heat is from the boiling and breathing of Hellfire.
[Sahih/Authentic] - [Al-Bukhari
Original Hadith
"«إذا اشْتَدَّ الْحَرُّ فَأَبْرِدُوا بالصلاة. فإن شدة الْحَرِّ من فَيْحِ جَهَنَّمَ».
[صحيح.] -"