Riyad as-Salihin, Book 9, Hadith 1143 (In-Book) ⓘ

Zaid bin Arqam (May Allah be pleased with him) reported: I saw some people performing Duha (prayers) in the early forenoon and warned them (saying): These people must know that performing Salat a little later is better. The Messenger of Allah said, "The Salat of the penitent is to be observed when the young ones of camels feel the heat of the sun (i.e., when it becomes very hot)."[Muslim].

عن زيد بن أرقم رضي الله عنه أنه رأى قومًا يصلون من الضحى، فقال‏:‏ أما لقد علموا أن الصلاة في غير هذه الساعة أفضل، إن رسول الله صلى الله عليه وسلم قال‏:‏ ‏ "‏صلاة الأوابين حين ترمض الفصال‏" ‏‏.‏ ‏(‏‏(‏رواه مسلم‏)‏‏)‏‏.‏