al-Bukhaari reports in his saheeh that Abu Hurayrah said: “Hell complained to its Rabb, saying “O my Rabb, some parts of me has consumed others.” So He allowed it to exhale twice, once in the winter and once in the summer. That is why you find extreme heat (in the summer) and extreme cold (in the winter)”.

al-Bukhaari also narrated from Abu Sa’eed (RA) that the Prophet (saw) said:
“Delay your prayers until it cools down, for the intensity of heat is from the exhaled air of Hell”. (Saheeh al-Bukhaari, Kitaab Bad’ al-Khalq, Baab Siffaat an-naar wa annaha makhluqah and Fath al-Baari 6/330. The author of Jaami’ al-Usool 10/517 attributed these two reports to al-Bukhaari, Muslim, and at-Tirmidhi).