NEW YORK (AP) - Airports in South Florida are returning to normal operations today. But airlines are warning of cancellations in and around New Orleans as Tropical Storm Isaac moves closer.

Airlines canceled more than 230 flights today, according to flight-tracking service FlightAware. The vast majority of those cancellations stemmed from the storm.

It's expected to grow into a Category 1 hurricane and hit land as soon as tomorrow.

American Airlines, which runs a major hub in Miami, was affected the most. It had nearly 150 cancellations in Florida this morning.

Yesterday, airlines canceled more than 850 flights, including nearly 500 from American.

Other Florida airports, including Fort Lauderdale and West Palm Beach, were responsible for most of the other cancellations.

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