The Dow Jones Industrials reversed and added 66.32 points to power into lunch hour at 34,684.56.
The much-broader index gained 10.11 points to 4,460.43.
The NASDAQ index jumped 20.31 points to 13,728.65.
A rise in energy prices helped energy stocks in the session. The energy sector of the S&P 500 advanced around 1%, led by Marathon Petroleum and Valero.
Meanwhile, Ford and Stellantis slid more than 1% as the United Auto Workers strike continued. General Motors, the other automaker facing off with the union, shed around 0.7%.
Goldman Sachs analyst Mark Delaney said Tesla earnings could take a hit from slimmer margins. Shares slipped about 2.5% in Monday’s session.
Traders are assigning a 99% chance that the Fed stays put when it releases its rate decision on Wednesday and just a 31% probability of a hike in November, according to the CME Group’s FedWatch tool, which gauges pricing in the fed funds futures market.
Prices for the 10-year Treasury regained lost strength, lowering yields to Friday’s 4.33%. Treasury prices and yields move in opposite directions.
Oil prices strengthened $1.20 to $91.97 U.S. a barrel.
Gold prices surged $3.30 to $1,949.50 U.S. an ounce.