Dallas is 1 hour behind Medellín
Best overlap: 9:00 AM to 6:00 PM in Medellín is 8:00 AM to 5:00 PM in Dallas.
Schedule calls for 9:00 AM to 6:00 PM in Medellín — your colleagues in Dallas will be online from 8:00 AM to 5:00 PM. With 9 hours of daily overlap, these two cities are an easy pairing; almost any reasonable hour works. Because Dallas and Medellín don't both observe daylight saving, plan to re-check the overlap around March and November.