Sunan Ibn Majah 678
سنن ابن ماجه#678SahihIt was narrated from Abu Hurairah that:The Messenger of Allah said: "When it is very hot, then wait for it to cool down before you pray, for intense heat is from the flaring up of the Hell-fire
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Al-AlbaniSahih
Muhammad Fouad Abd al-BaqiSahih
Shuaib Al ArnautSahih
Zubair Ali ZaiSahih Muslim
In-book reference: 2:12