(6) The Book of the Times (of Prayer)
كتاب المواقيت
(5) Chapter: Waiting To Pray Zuhr until It Cools Down When It Is Hot
(5) باب الإِبْرَادِ بِالظُّهْرِ إِذَا اشْتَدَّ الْحَرُّ ‏.‏
Sunan an-Nasa'i 500 
It was narrated that Abu Hurairah said:
"The Messenger of Allah (ﷺ) said: 'If it is very hot, wait until it cools down before you pray, for intense heat is a breeze from Hell.'"
أَخْبَرَنَا قُتَيْبَةُ بْنُ سَعِيدٍ، قَالَ حَدَّثَنَا اللَّيْثُ، عَنِ ابْنِ شِهَابٍ، عَنِ ابْنِ الْمُسَيَّبِ، وَأَبِي، سَلَمَةَ بْنِ عَبْدِ الرَّحْمَنِ عَنْ أَبِي هُرَيْرَةَ، قَالَ إِنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ ‏ "‏ إِذَا اشْتَدَّ الْحَرُّ فَأَبْرِدُوا عَنِ الصَّلاَةِ فَإِنَّ شِدَّةَ الْحَرِّ مِنْ فَيْحِ جَهَنَّمَ ‏"‏ ‏.‏
Grade :  Sahih (Darussalam)
Reference : Sunan an-Nasa'i 500
In-book reference : Book 6, Hadith 7
English translation : Vol. 1, Book 6, Hadith 501