5 days of Diwali celebration begins tomorrow, November 4, 2018. The first of these 5 days is celebrated as Dhan Teras. This day is also known as Dhanwantri Trayodashi, the appearance day of lord Dhanwantri who came out of the Ocean with a pot of amrita (nectar) in his hand on this day. Please see below exact dates and times for Dhan Teras and Diwali for India and USA (PST).
You can also find this information on my website here: https://ganesha-hanuman.com/vedic-calendar/