Opportunities that are marked as "forecast" are those that announce an upcoming tender or grant notice. These notices do not have a fixed project schedule or deadline in place as yet.
Those "open" are those that are accepting expressions of interest, proposals or bids, indicating that the competitive process of selection has begun.
Opportunities that are "closed" are not accepting expressions of interest, bids, or proposals. Note: when a Program report is marked as "closed", it means that the opportunity may have now moved to the accepting bids stage.
What's a program report?
A donor releases a program report before the tendering process begins. The report shares project details like background, components, total budget and possible sectors of engagement. These reports share insights on possible procurement opportunities that may arise in the future, though not all development projects require procurement procedures to be implemented. They don't get into the same level of detail that tenders do. A program report does not request proposals, and is not an opportunity that you can bid on, it aims to share the goals and scale of a project.
Read this article for further information on the differences between tenders, grants, and open opportunities.