What is the prescribed time for Dhuhr prayer, particularly during intense heat?

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The time for Dhuhr prayer begins after the sun has declined from its zenith, to the extent that the shadow is like the person when the heat is at its peak (when people cease extensive travel). In winter, this time is when the shadow moves from its position to the right edge of the observer. Delaying Dhuhr is recommended during intense heat to avoid praying during the peak heat (Al-Kayz) when people typically rest, as indicated by the practice of the Prophet, peace be upon him, and the instructions given to Mu'adh ibn Jabal.