U.S. oil firms see no impact from tropical storm

HOUSTON, June 29 (Reuters) - Tropical Storm Arlene was too far south and too weak to affect operations at U.S. Gulf of Mexico refineries, offshore platforms and drilling rigs, oil companies said on Wednesday.

Arlene, the first named storm of the 2011 Atlantic hurricane season, formed Tuesday afternoon in the Bay of Campeche off the Mexico's coast, was forecast to come ashore Thursday morning south of Tampico, Mexico.

BP Plc (BP.L) (BP.N) and Shell Oil Co (RDSa.L) both said on Wednesday that their operations in the Gulf were unaffected by Arlene. (Reporting by Erwin Seba and Kristen Hays; Editing by Lisa Shumaker)