The Prophet ﷺ said, "Wait for the heat to cool down before praying Zuhr, for the intensity of the heat is from the blazing of Hellfire."
حدثنا وكيع عن بشير بن سلمان
عن النبي ﷺ قال أبردوا بالظهر فإن شدة الحر من فيح جهنم
Its isnad is sahih. Bashir bin Salman Kindi is trustworthy, his hadith is found in Muslim and the Four (Sunan compilers). Qasim bin Safwan was deemed trustworthy by Ibn Hibban and Ibn Khalfun, while Abu Hatim was silent about him. The hadith has already appeared at 11510 and 11343. (2) In the printed edition, it reads "al-bashar," which is an error.