HOUSTON (Reuters) -The first storm to hit oil-producing regions of the U.S. Gulf of Mexico this year sent workers fleeing offshore oil platforms and cut some production.

A weather disturbance in the central Gulf of Mexico was expected to become a tropical storm on Friday. It was moving north at about 14 miles per hour (22 kmh) and could bring up to 12-inches of rain to the central U.S. Gulf Coast by Saturday, the National Weather Service said.

Equinor ASA on Friday said it had removed staff and shut production at its Titan platform, which is about 65 miles (105 km) off the coast of Louisiana. Chevron and Occidental Petroleum also removed staff and began taking precautions at their offshore oil and gas platforms.

“This is not that unusual to run evacuation flights this early in the season,” said Jason Glynn, director of operations at a Bristow Group offshore crew transport unit in Louisiana. “The last couple of years we’ve always had one softball like this early in the season.”

Chevron removed non-essential staff from three U.S. Gulf of Mexico oil platforms and fully evacuated a fourth that is about 150 miles sought of Louisiana. Output remains at normal levels, a spokesperson said.

“All of our facilities have plans to prepare for weather-related events and are implementing those procedures,” Occidental said on its website. It did not comment on production.

Other major producers including BP, BHP, Royal Dutch Shell and Murphy Oil said they were monitoring weather conditions but production had not been affected.

Louisiana Offshore Oil Port, the region’s only deep water oil export port, was operating normally. Offshore pipeline operator Enbridge also said it was monitoring conditions.

(Reporting by Gary McWilliams; Editing by David Gregorio)