Deleting a Forecast is straight forward!

Step 1: First, go to Forecast Register and find the Forecast you'd like to Delete. Click the Three Dots Menu ( ) against the Forecast you'd like to Delete and select 'Delete'. 

Step 2: After clicking Delete, you'll receive a popover notification based on the system's built in Business Rules, required due to the inter-dependencies with Contracts, Claims and Cash Flow. 

Note: If you Delete a Forecast, it's gone Forever - including all Cash Flow that may have been assigned to it!