This could signal trouble for stocks

Stocks have run into a bit of trouble lately, sliding more than 2 percent off recent record highs. And over the course of September, the CBOE Volatility Index, sometimes known as the market "fear index," has risen 36 percent. However, technical and fundamental indications could be pointing to further upside for the VIX, which could also lead to further pain for investors.

Ari Wald, head of technical analysis at Oppenheimer, says a rising VIX actually tend to be a signal to buy stocks. The problem, he says, is that the VIX hasn't risen quite high enough yet.

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"Your opportunities are when you see these VIX spike in an uptrend, and looking at the VIX, it's currently about 16. We would look at an area around 18 to 20 as a good opportunity to buy stocks. We're not there yet."

On the contrary, "there could be one more near-term setback in the S&P 500," he said.

Gina Sanchez of Chantico Global is also looking for a decline.

"We're looking for a drop in the S&P, and that's something we haven't really seen," even with a rising VIX. But "I do think that we are due for the S&P to cool off at some point."

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Sanchez's concern, however, is less the VIX and more market valuations.

"A lot of people are very concerned about where we are and where valuations are, myself included," she said. "Right now, stocks are well out above their skis."

But like Wald, Sanchez is longer-term bullish.

"Would I use a significant correction to get into the market? Probably. I do actually think that's where you want to be for 2015," she said.

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