Jeremy Siegel: My Dow 18K prediction only 50-50 now

Dow 18,000? Chances are 50-50: Siegel

It looks like the stock market hit its recent bottom last week, long time stock bull Jeremy Siegel told CNBC on Friday. But the Wharton School professor of finance said his prediction for the Dow to reach 18,000 by year end is now only 50-50.

"Perhaps I've been sticking my neck out too much," Siegel joked in a "Squawk Box" interview, but added that 18,000 still appears more likely than it did last week. He also pointed to the historic strength for stocks in the months of November and December.

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Following Thursday's strong 216 point rally, the Dow closed at 16,677, which puts blue chips more than 7 percent from 18,000. The Dow is about flat for the year after the recent downturn.

Stocks were even higher on Thursday—before the diagnosis of a New York City Ebola case pared strong gains, and in turn, put pressure on global markets Friday.

Despite the New York City scare, Siegel sees the Ebola effect on the market receding. He said there's much less anxiety about this patient than the fatal case in Texas and the situation in West Africa.

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Tipping point for markets

By contrast, Peter Weinberg, co-founder of Perella Weinberg Partners, sees Ebola as a possible tipping point for the market, which was already dealing with unrest in the Mideast and slowing economies in Europe and China.

"Little things make a big difference in the market. It's never that one thing. It's always just the accumulation of concerns," Weinberg told CNBC's "Squawk Box" in a separate interview Friday.