Forget about any CB action. The days of don't fight the FED were or are about to be extinguished. They had their chance to be proactive and missed the opportunity. At the very most any rate hike or cut is going to achieve short term results (and even this is questionable) but at the same time have disastrous consequences both in the medium and long term aka their job description is that of damage limitation...a task they will also miserably fail to accomplish. Watch the markets instead coz it's what even the central bankers are doing anyway.
The CB's are behind the curve now - not that they are willing to admit it - and the party has to come to an end. If anything huge implodes in Q4, things will turn south pretty fast and 2017 is when most of the damage will be done.
World trade has been shrinking for the longest while. The juggernaut that is the German export machine is choking coz of this strain. A US recession is all but the last nail in the coffin to this business cycle. Whether it goes down on its own accord (thanks to its own excesses) or under the weight of a contagion from elsewhere is a flip of the coin kind of probability.
China that so ably acted as the saviour during the GFC is this time around part of the problem and a big part of the problem for that matter.
If you thought GFC was bad, buckle up, this is not going to be a pleasant experience. I cannot emphasize how important holding your nerve will be if one is to survive the carnage and/or thrive there after.
The main purpose of the stock market is to make fools of as many people as possible.