As we head into the homestretch of summer and the Labor Day holiday weekend, investors are anxious to see if next week brings elevated volume and the reinforcements to help the bulls break out. However, there’s no doubt that the bears are lurking in the wings to drive stocks down hard, given the right scenario.

Volume has elevated somewhat this week, as Wednesday saw more trading volume than we have seen since the beginning of the month—likely due to the release of the FOMC minutes (both in anticipation and aftermath). In any case, equity holders have been loath to sell. Mild intraday weakness continues to be met with buying.

We’re coming down to the final sleepy weeks of a relatively uneventful summer in the equity markets. Volume is quite low, as is expected this time of year with investment managers in vacation mode. Nevertheless, the S&P 500 has now recovered all of its losses since the “Sell-in-May” crowd hit the market hard, sending the S&P 500 falling 9% from a close of 1406 on May 1 to 1278 on June 1.

U.S. equities continue to shrug off worrisome global economics and the doomsday prognostications. The Dow, S&P 500, and Nasdaq are now all above psychological resistance levels of 13,000, 1400, and 3,000, respectively. Even Europe and China have seen a sustained bounce in equities. But everyone is wondering, how long can this continue given the dicey global economic situation?

Bulls have refused to let the market break down. Last week, the ECB’s Mario Draghi came to the rescue by pledging to do “whatever it takes” to support the euro, which launched a big rally to close the week. Still, investors have been eagerly anticipating an announcement of something more concrete, like some bold new action from the central banks, i.e., more global liquidity.

Markets attempted to rebound on Wednesday after two days of fear and loathing, but extreme weakness in Apple (AAPL) held back the Nasdaq and S&P 500 while the Dow was able to finish positive. Whether this is just a dead cat bounce remains to be seen. Without a doubt, this week has changed the technical picture from bullish to iffy.

Markets have been signaling a willingness to look past the deluge of troubling news and move higher. This is bullish behavior. On Tuesday, market psychology displayed its positivity as initial weakness on bad news was quickly reversed. Rather than demanding that the Fed initiate a QE3, investors seem to be happier with indications from the Fed that the economy might be able to muddle along without it.

On Wednesday, the S&P 500 rallied hard in the last 20 minutes to finish right near the flat line, but it still closed with a fractional loss, which makes it the fifth straight loss since last week’s Independence Day patriotic rally. It is now testing technical support at a level of prior-resistance-turned-support.

Stocks have rallied since Friday, largely due to some promising developments out of Europe toward addressing their sovereign debt issues and shaky banks. As I said last week, global investors hoped for a sign of commitment from EU leaders at their latest summit to stimulate growth, create a banking union, and debt mutualization (e.g., Eurobonds). What they got was pretty close. And U.S.

I don’t know about you, but I’m getting a lot of auto-response emails from folks in the investment world who are on vacation these days. Yes, the summer doldrums have set in, often leaving junior portfolio managers—without seniority, vacation time, school-age children, or much in the way of discretionary authority—to mind the store.