S&P-500 chart highlighting volume trend.The negative divergence on MACD - on the daily charts of the S&P-500 and the Dow Industrials - was the previous 'Chart in Focus.' Despite hanging on well after the markets themselves had moved to new highs, that potential sell signal has finally become defunct. If you look purely at the trend and ignore other aspects such as the bollinger bands, volume levels, momentum indicator readings and so on, you'd get the feeling that its all systems go, and that a continuation of the rally is inevitable.

No doubt, it makes absolutely no sense to fight the trend; it never is. And traders better have a good reason to be opening any short positions, at this juncture. However, whilst trading with the trend makes sense, traders who are successful over the long run also realize that it is important to be prepared for any and all eventualities. After all, markets often reverse course just when most market watchers least expect it to.

So, in the interest of playing devil's advocate, as well as keeping abreast of all potentialities, we're going to focus in on the trend in volumes on the S&P-500, over the next few sessions.

You'll notice that the average volume traded over the last three weeks of August, when the markets were trading within a channel that was gently sloping upwards, was around 4.3 billion. Then, there was a dip in the beginning of September, at around the same time the markets began the latest climb.

The farther this move has gone, the higher volumes have gotten. Over the past two sessions, volumes have been as high as 5.3B and 5.8B, respectively. Thats not exactly extreme as yet but if volumes start to come in consistently at, say, 6.0-7.0B, we'll need to consider the possibility that this is a blow-off top in-the-making.

The fact that the rise in volumes has come absent any earth-shattering news is evidence that a bit of "panic buying" is creeping into the markets, as investors who ignored the possibility that the March bottom was a turning point, now come flooding in, in the hope that the trend continues and they get a piece of the action.

Sustainable rallies occur on gradually rising or stable - or even slightly declining - not sharply rising volume conditions. So this is something for traders to just keep an eye on, as they enjoy making hay while the sun shines.