All reliable information says that the airports in Bangkok will be open from 4 December.
As a first port of call, anyone worried about this weekend's departures should contact their airline to see if they are still scheduled to fly. If they are then there is no need for them to cancel their tours, travel overland to Bangkok, or try to join the tour at an alternative point.
It is possible though that with such a backlog, some airlines may not resume flights until after the weekend. If you are due to travel this weekend, and that is the case for your airline, then please contact us or your travel agent for the most up to date information on how you may join your tour and what options are available for you.