Former Federal Reserve governor Kevin Warsh predicts that the Trump economy will only continue to strengthen because of the solid economic fundamentals fueling the growth.

President Donald Trump’s corporate tax cut and his business deregulation efforts are not a “sugar high,” Warsh told CNBC.

Most economists “never thought the economy could grow this fast,” says Warsh, who had been on Trump’s short-list for Fed chairman.

Growth estimates for the third quarter are above a 3.0 percent annualized rate, with an average of 3.5 percent growth for the first nine months of 2018. The economy grew at a 4.2 percent pace in the second quarter.

“Today the economy is the strongest it’s been since it’s been in the U.S. since 2004” when growth was 3.8 percent, Warsh said. “At the end of this year, we may be saying the economy is the strongest since 1999,” Warsh predicts.

Warsh isn't alone in his economic optimism.

The U.S. economy is growing at a 4.1 percent annualized rate in the third quarter following the government’s construction-spending report and other recent economic data, the Atlanta Federal Reserve’s GDPNow forecast model showed on Tuesday.

The GDPNow model estimate for real GDP growth (seasonally adjusted annual rate) in the third quarter of 2018 is 4.1 percent on October 1, up from 3.6 percent on September 28.

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