What's 'Quadruple Witching?'

Investors should brace for a bumpy ride during Friday’s trading session due to "quadruple witching," Dodge Dorland, AB chief investment officer from Landor Capital Management, told CNBC.

But historical averages show that the major indexes have about a two-in-three chance of closing in the green.

“Bumpy, volatile, a lot action in the first half hour and then probably very quiet between 10.30 (am New York time) and 2.30, 3 o’clock. And then again, at the end of the day we’ll see some more action,” Dorland said.

Quadruple witching happens on the third Friday of every quarter and is the simultaneous expiring of stock index futures, stock index options, stock futures, and stock options.

This is the 26th such quadruple witching to happen since single stock futures were launched back in December 2002.

The Dow Jones Industrial Average has gained 65 percent of its previous quadruple witching sessions, with an average modest gain of 0.4 percent. The S&P 500 has gained 62 percent of the time, while the Nasdaq rose 58 percent of the sessions.

The highest gain during a quadruple witching session was from the S&P on Sept. 19, 2008, when the index racked up a 4 percent surge. Its average gain is a meager 0.3 percent, however. 

The VIX index of volatility has ended higher 42 percent of all the previous quadruple witching sessions, suggesting they are less volatile than a normal trading day. However, quadruple witching tends to cause short periods of high volatility. 

Dorland expects a “little selling pressure” during the session, but says that any dips should be viewed as buying opportunities.

- Watch the full Dodge Dorland interview above.

• Slideshow: Market Mayhem

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