Crude oil futures rose Monday at the New York Mercantile Exchange, buoyed by a developing tropical storm in the Gulf of Mexico and continuing tensions between the West and Iran over the latter's nuclear-research program.

Texas light crude for August delivery added $2.16 to $131.04 a barrel, and Brent crude was up $2.73 at $132.92 a barrel. Reformulated gasoline futures gained 5 cents at $3.22 a gallon, and heating oil tacked on 6 cents at $3.75 a gallon.

Tropical Storm Dolly, which formed in the Caribbean Sea over the weekend, is beginning to veer into the southern Gulf of Mexico, drawing the attention of energy traders as it does so. According to Edward Meir, energy analyst at MF Global, the storm will likely track the northern Yucatan peninsula without harming the Gulf's energy infrastructure. However, some weather models are showing that the storm could ultimately aim for Texas.

Elsewhere, weekend talks between Iran and Western nuclear negotiators failed to reach a compromise, but instead ended with a "reiteration of previously stated positions," Meir said.

Meanwhile, integrated energy stocks mostly advanced. ConocoPhillips ( COP - Get Report) added 2.3% to $85.86, Hess ( HES - Get Report) was up 6.3% at $103.98 and PetroBras ( PBR - Get Report) gained 2.8% at $59.66. Exxon Mobil ( XOM - Get Report) was better by 1.8% at $82.98.

In the E&P space, Chesapeake Energy ( CHK - Get Report) was up 2.8% at $55.84, and Whiting Petroleum ( WTI - Get Report) advanced 4.7% to $51.42.

The U.S. Oil ( USO - Get Report), an exchange-traded fund that closely tracks the performance of near-month WTI contracts, rose 2.1% to $106.67.