Musannaf Ibn Abi Shayba 36:494

Hafs narrated to us, from Ja’far, from his father, who said: Safiyyah went out when the Prophet, may Allah bless him and grant him peace, had passed away, and she was waving her garment—meaning she was gesturing with it—while she was saying: "There have been tidings and disturbances after you; had you been present, the calamities would not have been so great."