U.S. stocks surged Monday to start the fourth quarter amid sharp declines in recent weeks.

The Dow Jones Industrial Average rose 765.38 points, or 2.66%, to 29,490.89. The S&P 500 rose 92.81 points, or 2.59%, to 3,678.43, and the Nasdaq Composite was up 239.82 points, or 2.27%, to 10,815.43.

It was the Dow's best day since June 24 after its worst month since March 2020. All three indices have fallen for three consecutive quarters this year.

Bond yields are falling, including on the 10-year Treasury note. The benchmark bond closed down 15 basis points to 3.647% on Monday. The dollar also fell against other major currencies.

Concerns appear to be cooling since the Federal Reserve's aggressive interest-rate hikes to stifle inflation.

"As a result, we're seeing yields come down, we're seeing the dollar weaken," Sam Stovall, CFRA chief investment strategist told CNBC. "Those factors are contributing to the move we're seeing today."

Some of the stocks that saw gains included Apple (AAPL), which closed at $142.45, up $4.25, or 3.08%. Qualcomm's (QCOM) price of shares rose $4.24, or 3.75%, to close at $117.22.