U.S. Gulf of Mexico oil and natural gas producers were monitoring powerful Hurricane Felix as it churned through the Caribbean Sea on Sunday, but none had reported reduced offshore production or evacuated workers to onshore locations.

Felix was forecast to follow the path taken last month by Hurricane Dean across the southern Caribbean into the Yucatan peninsula and then through Mexican offshore production areas in the Bay of Campeche.

Unlike Dean, computer models forecast Felix will move northwest from the eastern Bay of Campeche before making final landfall as early as Friday on the east coast of Mexico.

Leading U.S. refiner Valero Energy Corp (VLO.N) said major process units at its 275,000 barrel-per-day (bpd) refinery were operating normally as Felix passed 50 miles to the north of the Caribbean island of Aruba, the company said on Sunday.

"We expect the main production units to keep operating," Valero spokesman Bill Day said. "We don't expect there to be an impact on production."

Felix has strengthened throughout the day into a Category 4 storm on the five-step Safir-Simpson scale. The storm had sustained winds of 138 miles per hour.

Oil and natural gas company representatives available on Sunday said decisions to begin taking workers who are not essential to production from offshore platforms would likely not be made before Tuesday.

Evacuations would only begin if the storm turned to the north targeting production areas off the U.S. Gulf Coast.

Dean's path through the Bay of Campeche led Shell Oil Co's (RDSa.L) joint-venture 334,000 bpd refinery in Deer Park, Texas, to cut production levels when partner Pemex, the Mexican state oil company, was forced to shut 2.65 million bpd in Bay of Campeche oil production for a week.

Pemex is one of the top three suppliers of U.S. oil imports.