One of the accidents happened at around 6pm, after the signal eight was issued.
A 31-year-old motorcyclist hit a lamp post after ramming a kerb as he approached Shek O beach.
He sustained serious head injuries and was certified dead at hospital.
Separately, a 57-year-old man died in Tin Shui Wai at around 4pm.
The man was driving towards Yuen Long Highway when he reportedly lost control of his truck and overturned.
The driver was trapped, sustained head and limb injuries, and was certified dead at hospital.