US stocks rally amid Yellen speech, GDP data

US stocks ended higher Friday, as investors assessed comments from U.S. Federal Reserve Chair Janet Yellen amid newly-released U.S. economic growth data.

The Dow Jones Industrial Average rose 44.93 points, or 0.25 percent, to 17,873.22. The S&P 500 added 8.96 points, or 0.43 percent, to 2,099.06. The Nasdaq Composite Index gained 31.74 points, or 0.65 percent, to 4,933.50.

Yellen said at Harvard University Friday that an interest rate hike in the next few months would probably be appropriate if economic data improve.

"Yellen surprised us all by saying a hike in the next few months is appropriate. She was not expected to discuss policy today. Her tone and comments were similar to Bill Dudley's, but her words carry more weight," said Chris Low, chief economist at FTN Financial, in a note.

On the economic front, U.S. real gross domestic product (GDP) increased at an annual rate of 0.8 percent in the first quarter of 2016, higher than the advance estimate of 0.5 percent, according to the second estimate released by the Commerce Department Friday.

Meanwhile, the final reading of consumer sentiment index published by Thomson Reuters/University of Michigan came in at 94.7 for May, missing market consensus.

For the week, all three major indices posted solid gains, with the Dow, the S&P 500 and the Nasdaq jumping 2.1 percent, 2.3 percent and 3.4 percent, respectively.

U.S. stock markets will be closed Monday for the Memorial Day holiday.