American Express warning about the economy, earnings outlook

After the bell, credit card issuer American Express is warning about a weakening U.S. economy and boosting its loan loss reserves. Specifically, Amex said it "is seeing signs of a weaker U.S. economy" with "negative credit trends among U.S. consumers during December, particularly in California, Florida and other parts of the country most affected by the housing downturn." It's taking a pretax charge of $440 million in Q4 to boost reserves, and forecasting earnings per share from continuing operations of 70 cents to 72 cents. That's below the 73 cents the company earned a year ago. Managed portfolio delinquencies climbed to 3.2% in Q4 from 2.9% in Q3. Competitor Capital One, for its part, warned on its earnings earlier today.