Portland is 19 hours behind Melbourne
Best overlap: 8:00 AM to 1:00 PM in Melbourne is 1:00 PM to 6:00 PM in Portland.
Schedule calls for 8:00 AM to 1:00 PM in Melbourne — your colleagues in Portland will be online from 1:00 PM to 6:00 PM. You share roughly 5 hours a day. That's enough for regular meetings, but treat the window as prime time and guard it. Don't get caught out: Portland is the previous day from Melbourne, so "tomorrow" means different things to each team.