With the recent action in the stock and bond markets, investors are right to be a little bit concerned right now, Burns McKinney told CNBC on Friday.
"Stocks are a little bit expensive across every factor, whether it's price to sales, price to earnings … [or] market cap relative to the economy," the chief investment officer for Allianz NFJ Investment Group said in an interview with "Power Lunch."
"And it's not just that. Other markets are also showing a little caution."
For example, the 10-year Treasury yield has pulled in and the yield curve is getting flatter. Meanwhile, equities are "priced for complacency," he noted.
"Usually when there's a disagreement between what the bond markets are saying and what stocks are saying, typically the bond investors are right, and they seem to be showing concern."
That concern may be about President Donald Trump's reform agenda, the French election or geopolitical risks in places like North Korea or Syria, McKinney explained.
Reclusive hedge-fund legend Paul Tudor Jones also recently had a warning about the market in a closed-door meeting at Goldman Sachs, according to Bloomberg.
He said a chart of the market's value relative to the country's economy should be "terrifying" to central bankers, namely Federal Reserve Chair Janet Yellen, Bloomberg reported. CNBC has also confirmed these comments with a source who was there.
The trader said that low interest rates instituted by central bankers around the world have ballooned U.S. stock market valuations back to 2000 levels, right before the dot-com bubble burst and shares plunged.
Shannon Saccocia, head of asset allocation and portfolio strategy with Boston Private Wealth, dismissed the idea of judging the market based on a single chart.
"It's inaccurate or inappropriate to look at one particular chart or piece of information as the indication of the overall strength of the market," she told "Power Lunch."
That said, she believes stock valuations are somewhat stretched.
"The reality is that the stock market is anticipating some positive moves here, whether it's tax reform or potential improvement in the European economy in the back half of the year," Saccocia said.
She believes there could be a "small correction" this summer if there is another delay in tax reform.
—CNBC's John Melloy contributed to this report.