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It could be a long, hot summer for housing stocks

The homebuilders tend to lag in the summer months, Goldman Sachs' options team said Wednesday. Goldman showed that the SPDR Homebuilders ETF (XHB), which contains a bevy of housing-exposed stocks, has traded "consistently lower" in the May-to-August period, dropping in seven of the past nine years, for a median decline of 7.5 percent.

Erin Gibbs, equity chief investment officer at S&P Capital IQ, said that the even stronger trend is in May and June, when "there's a clear negative return, both in relative terms versus the S&P 500, and in absolute terms. … So those are the months to go ahead and short or to use your options" to construct bearish positions.

Such has not been the case this May, with the XHB rising 2.1 percent in the first nine trading days of the month. And therein may lie the opportunity.

"We believe the recent outperformance provides a compelling entry point for investors to buy put spreads," Goldman's options team wrote, referring to a bearish options strategy with measured risk. Burnishing their case is the fact that "options investors are not pricing in downside risks to homebuilder stocks ahead of summer," meaning that put options are attractively priced.

While that may make for a smart trading strategy, historical anomalies without explanations are just that—exceptions. But Goldman says there's a decent fundamental explanation for the historical trend.

The underperformance comes "largely as investors buy the typically highly correlated group ahead of the highly anticipated Spring selling season, and then sell once the news has been disseminated," the research team said.

Megan McGrath, who covers the homebuilders for MKM Partners, told CNBC she has also noticed the historical underperformance, with May, June and especially July tending to disappoint. And she agrees that this summer could bring much of the same.

"With the spring selling season coming to a close and some new concerns about rising yields and mortgage rates, we think it could be difficult for the shares to find a meaningful positive catalyst in the early summer," she wrote.

McGrath is neutral on the sector as a whole, forecasting flat performance in 2015.

But even bullish analysts say the summer could bring rocky waves.

"The homebuilders typically experience a lot of seasonality—no surprise there," wrote Robert Wetenhall, who covers homebuilders and building products stocks for RBC Capital Markets. And even though the fundamentals have been strong in terms of overall home selling, "the builders already started to outperform in April, which suggests that investors aren't that focused on fundamentals."

"I like the group long-term, but agree that we could see near-term volatility as we roll into the summer," Wetenhall concluded.

CORRECTION: This version corrected the year of McGrath's forecast.

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