Departing on a Friday is a good option for securing a great price. You can expect to save up to 133% when planning your travel around this day of the week.
Due to multiple factors, expect to potentially pay more when booking in December. For low rates, August can be a great choice for travel to St Thomas. Flights to St Thomas from Oakland in August are about $412 on average during August, but can be found for as low as $157.
Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Oakland to St Thomas as you normally would.