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HOUSTON, Aug 15 (Reuters) - Workers for some Gulf of Mexicooil and gas operators were being evacuated from offshorefacilities on Thursday as a low-pressure system threatened tostrengthen into a cyclone but production was not interrupted.
The U.S. National Hurricane Center said a weatherdisturbance in the northwestern Caribbean Sea had become lessorganized overnight and had a 50 percent chance of becoming atropical cyclone in the next 48 hours, down from a 70 percentchance.
"Development of this system is not anticipated while itmoves over land, but there is still potential for developmentonce the disturbance moves over the Gulf of Mexico on Friday,"the Center said in its latest bulletin on Thursday.
Mexico's state oil monopoly Pemex said it wasmonitoring the storm but had no plans to evacuate itsinstallations, including its platforms in the Bay of Campeche atthe southern tip of the Gulf of Mexico, where it extracts 80percent of its crude output.
Marathon Oil Corp said on Thursday it was evacuatingworkers not essential to production from its Ewing Bankplatform, which can produce up to 9,700 barrels per day of oiland 8.2 million cubic feet per day of natural gas. Such workerswould include cooks and maids.
"Marathon Oil's operated production has not been impacted atthis time," spokeswoman Lee Warren said.
BP Plc said it was evacuating nonessential workersfrom oil and gas platforms. It has four platforms in the centralGulf, including Thunder Horse, the biggest in the world.
The company said it had temporarily halted contracteddrilling rigs, but platforms were still working.
"Oil and natural gas production at all BP-operated platformsremains online at this time," the company said.
Destin Pipeline Co LLC also said pipelines in the Gulf ofMexico operated by BP were evacuating nonessential workers. Thecompany said it would continue to accept natural gas flows asweather conditions permit.
Other companies said they were monitoring the storm.
