"Markets are trading at valuation extremes at this point," he said.
Unofficially, the Dow Jones Industrial Average rose 188.57 points, or 0.58%, to 32,485.59, the S&P 500 gained 40.46 points, or 1.04%, to 3,939.27 and the Nasdaq Composite added 329.84 points, or 2.52%, to 13,398.67.
Fewer than expected Americans filed new claims for unemployment benefits last week as vaccinations allow more segments of the economy to reopen.
"The drop in jobless claims is another win for the week, and a solid sign that we're making some strides toward pre-pandemic life," said Mike Loewengart, managing director of investment strategy at E*Trade Financial.