One top technical analyst sees more downside risk than upside reward for the S&P 500 in the months ahead.

Matt Maley, equity strategist at Miller Tabak, is worried about how the index has behaved over the past six months. Particularly, Maley notes that the S&P 500 has tested its 100-day moving average repeatedly before rallying up to what he sees as an upward-sloping resistance line.

"The problem is when we rally and break to new highs, which we've done several times, each time it's only a slight break of 1 percent or so," he said. "Although it's kind of an upward-sloping channel there, my concern is that we haven't been able to break out in a significant way."

A meaningful breakout would occur if the S&P 500 broke out above 2,150. "That's kind of a magic number—1 percent above the old high," he said. "If we can break above that, that will be a positive. But with interest rates moving higher and economic growth being pretty mediocre, it's going to be tough to do that, I'm afraid."

Maley sees more turbulence in the months ahead but sees some hope by the end of the year.

"The near-term risks are greater than the near-term potential," he said. "The upside could be 1 to 3 percent where the downside is 7 to 10 percent, although by year-end, we'll probably recover from a more meaningful pullback."

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