Correction won't derail bull market: Piper Jaffray

Bull market still intact: Technician
China handing US markets correction: Pro
September swoon looms?

The selloff at Tuesday's open on Wall Street put the Dow industrials and Nasdaq back in correction territory.

Despite the drop, and the dramatic plunge early last week, Piper Jaffray senior strategist Craig Johnson told CNBC's "Squawk Box" the selling won't derail a long-term trend higher.

"There's no question that a lot of technical damage [has been] done," he said before Tuesday's opening bell, but added the secular bull market in stocks remains intact. The term secular bull market refers to a market that moves higher over the long haul, even with periodic corrections and or bear market conditions.

Johnson emphasized the primary trend still looks higher, and he advised investors to buy the dips. "I expect us to find the lows here somewhere soon. I'm not saying today is going to be the day, but I think in the next few weeks here."

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Alison Deans at AA Deans Advisory said in a separate "Squawk Box" interview Tuesday however, that it's too early to buy the dips. She feels there's more downside to go before the market finds its bottom. "I don't think it's dipped quite enough yet."

New data on China's manufacturing sector showed a further loss of momentum, which sparked another selloff in global markets. The Dow Jones industrial average, and Nasdaq composite each lost more than 6 percent in August, heading into September, which has a long-running history as the worst-performing month of the year for stocks.

"It almost feels like the market has been looking for a correction and China is handing it to us," Deans said.

But even with Tuesday's early decline, the S&P 500 did not return to last week's correction levels, defined by declines of at least 10 percent from record highs.

Deans said she's not worried about the U.S. economy suffering directly from China's problems.

Growth in America should continue to improve unless consumers get scared and pull back spending, she argued—but warned about an indirect impact on corporate profits.

James Liu, global market strategist at J.P. Morgan Funds, told CNBC on Tuesday that the slowing Chinese economy has been widely telegraphed and priced in the market. Only a really hard landing for the Chinese economy would present a compelling reason to shift his expectations for continued U.S. growth.

"A hard landing is not a 5 percent [growth] number. It's zero percent or negative growth rate," he said—but added the U.S. should be rather distinct from these global problems. "That should cause some stability in the short run, ... this morning not withstanding. "

Liu said investors should buy the dips—not because stocks might get a little cheaper but because the prospects for the U.S. stock market remain solid. In fact, he added, valuations are more attractive now than at the start of the year.

"I don't think we're stretched at all at this level about the way people feel about this market," he said.