Chevron warns on Q4 profit, shares drop (Reuters) - Chevron Corp (CVX.N) warned that fourth-quarter profit would be significantly below the previous quarter, with production still falling short of prior expectations and its refining operations about breaking even. Shares of the second-largest U.S. oil company fell more than 2 percent in after-hours trading to $105.21, or about $5 below the record high they hit last week. Chevron said "upstream" earnings from oil and gas production would be comparable to the $6.2 billion in the third quarter, but only before accounting for foreign-exchange impacts. "Full third quarter earnings included foreign exchange gains of nearly $450 million, compared to a loss anticipated in the fourth quarter," Chevron said in its quarterly interim update. Analysts had previously been looking for an overall fourth-quarter net profit of $6.6 billion, or $3.33 per share, according to the average on Thomson Reuters I/B/E/S. This compared with $5.3 billion a year before and $7.8 billion in the third quarter of 2011. Chevron's international oil-equivalent production rose to 1.98 million barrels per day (bpd) in the first two months of the quarter from an average of 1.94 million for all of the third quarter, the company said on Wednesday. But U.S. production in October and November fell to 660,000 bpd from 662,000 in the third quarter, it said. In total, Chevron had 2.64 million bpd of oil-equivalent production for the first two months of the quarter, up from 2.60 million in the third quarter but sharply below its full-year 2011 forecast of 2.73 million bpd. The only period in 2011 that Chevron has topped the annual estimate was the first quarter. On the refining side, Chevron said Gulf Coast margins fell "substantially" in the fourth quarter from the three months before, citing industry figures showing they had been cut in half. Downstream margins were also weaker outside the United States. On top of that, U.S. refinery input fell by about 180,000 bpd to 717,000 bpd, largely because of a major turnaround at its refinery in Richmond, California. So downstream earnings overall were expected to be near breakeven, Chevron said, without the help of a $500 million gain recorded the previous quarter from its sale of its UK refinery. In addition, the San Ramon, California-based company said total net charges for the fourth quarter would be "notably higher" than its general guidance range of $250 million to $350 million. Chevron will report earnings on January 27. Reporting by Braden Reddall in San Francisco; Editing by Bernard Orr