The Fed Chairman speaks Aug 25

Janet Yellen speaks on Friday at the Kansas City Fed's Jackson Hole symposium. The annual event is a traditional spot for central bankers to set the agenda for the final stretch of the year.

That said, there are no guarantees and a clue in the schedule suggests it might not be Yellen who makes a splash. The topic of her speech is 'financial stability' which is the kind of thing that often focuses on regulation.

More likely, it means she will speak about the start of the Fed's QE runoff. At this point, most expect a September announcement to be a formality and the start of the program to be smooth. That said, the Fed will be desperate to avoid sparking any volatility and is likely to be laser focused on execution in the months ahead.

On the economy, the Fed is likely confused. They made some rosy forecasts on inflation based on upticks in consumer and business surveys at the start of the year. Those surveys haven't translated into good economic growth but the main line of thinking from Yellen and the core of the FOMC is that it's only a matter of time.

Eventually, they might have to give up but for now, Yellen will want to wait and see for a few more months. If anything, that's likely to be the signal at Jackson Hole but it's not the kind of thing that will spark much of a market reaction.