U.S. stocks hit new all-time highs last week, with four consecutive weeks of gains, but one chief investment strategist warned investors that the recent rally could cool as temperatures do.
"We remember all those romances back at summer camp; they were exciting, they were hot, they were thrilling but when summer camp ended, they ended," Michael Arone, State Street Global Advisors chief investment strategist told CNBC's "Squawk on the Street" Monday. "When summer turns to fall, this particular rally will begin to slow down."
The record highs have been driven by surprisingly positive corporate earnings, Arone said. Of the S&P 500 companies reporting as of last week, roughly 65 percent beat estimates, according to Thomson Reuters.
The Federal Open Market Committee meets this week, and any nod towards higher interest rates in 2016 could pause the equity rally, Arone said.
"It wouldn't shock me at all if we actually see that this week," he said. "That would give a bit of a headwind to this particular rally."