Sunan Ibn Majah 682
It was narrated from Anas bin Malik that:
The Messenger of Allah used to pray 'Asr when the sun was still hot and high, and if a person were to go to the suburbs (of Al-Madinah) he would be able to reach it while the sun was still hot and high.
حَدَّثَنَا مُحَمَّدُ بْنُ رُمْحٍ، أَنْبَأَنَا اللَّيْثُ بْنُ سَعْدٍ، عَنِ ابْنِ شِهَابٍ، عَنْ أَنَسِ بْنِ مَالِكٍ، أَنَّهُ أَخْبَرَهُ أَنَّ رَسُولَ اللَّهِ ـ صلى الله عليه وسلم ـ كَانَ يُصَلِّي الْعَصْرَ وَالشَّمْسُ مُرْتَفِعَةٌ حَيَّةٌ فَيَذْهَبُ الذَّاهِبُ إِلَى الْعَوَالِي وَالشَّمْسُ مُرْتَفِعَةٌ ‏.‏