I had a different piece planned this month but a couple of weeks ago I decided to toss it on the backburner and start a landscape piece instead. When the urge to draw rocks and waves strikes, I see little reason to ignore it.
For those of you who follow along for art advice, I want to point out how absurdly simple the painting is at this stage. Whenever I mentor artists, I try to stress the importance of how the work begins. Trying to take an unbalanced mess and bring life to it is an incredibly risky way to work. It's much easier to begin with simple expressions of what you want to accomplish and then layer all the more complex elements on top of it.
There is nothing clever, precise, or especially creative about this phase of the process. It's a few quick waves of the hand. And yet, everything in here will ultimately contribute to the final product. The key to making such a simple bit of work valuable is to do it with total earnestly. You have to be willing to declare "this is what I want to paint" with a level of confidence that commits you to dozens of hours of tedious work.