Muwatta Imam Malik (Riwayat Ibn al-Qasim)

It is narrated from Sayyiduna Abu Hurairah, may Allah be pleased with him, that the Messenger of Allah, peace and blessings be upon him, said: "When the heat is intense, perform the prayer after it has cooled down, for the severity of heat is from the breath of Hell." And he, peace and blessings be upon him, explained that the fire (of Hell) complained to its Lord, so it was granted permission for two breaths every year, one in the winter and the other in the summer.