Delta, Southwest, American Airlines Cut Forecasts, an Early Alarm About Consumer Spending

Airlines flashed an early-warning signal on Tuesday, suggesting that consumers and businesses were starting to get nervous amid wider economic and political uncertainty.

Several carriers cut their financial forecasts for the first few months of the year, saying that revenue would be weaker than expected. They pointed to a number of reasons: bad weather, high-profile plane crashes, and less spending by consumers, businesses and the federal government.

“We just went through a little bit of a…