I've been told by some people that a holiday is a bad day to do a prompt. Their reasoning is that no one is going to be writing on a holiday simply because it is a holiday.
I think most writers feel that they are at their best when they sit down to write everyday. It doesn't matter if it's tough writing that day, the point is they did the work. They kept themselves on track and moving forward. On some holidays, especially those that families like to spend a lot of time together or require a lot of kitchen time, it can be nice to let your mind run wild for a little while. A writing prompt can do that. Just a nice little exercise to keep your creativity and writing in top form.
So for St. Patrick's Day I thought something lush and green would be appropriate. Who's looking out? What's out there? Where are they? There's no right answer - just start writing and find out for yourself!