Shaykh Bin Baz was asked:
“Is it allowed to raise the hands while supplicating for the deceased?”
“It has come in some Ahaadith that the Prophet (ﷺ) raised his hands when he visited the graves and supplicated for its people. It was established
from the Hadith of Aisha (may Allah be pleased with her) that the Prophet (ﷺ) visited the graves and supplicated for them and raised his hands. Report by Muslim in his Saheeh”.
End translation. [Majmoo’ al-Fatawa (13/338)]
Faisal Ibn Abdul Qaadir Ibn Hassan