Aviation officials in Houston said flights at George Bush Intercontinental Airport would be suspended at 2 p.m. CDT on Friday and 3:30 p.m. CDT at the smaller Hobby Airport.
Houston-based Continental Airlines Inc., whose largest hub is at Bush Intercontinental, said it might also stop flights early Friday afternoon at other airports along the Gulf. It said service in Houston and any other affected cities was likely to resume Sunday.
The airline said its Continental Express and Continental Connection regional flights, which use smaller aircraft, would stop Houston flights even earlier on Friday -- between midmorning and midday.
Other airlines that operate flights in and out of Bush Intercontinental include AMR Corp.'s American Airlines, the nation's largest carrier; Delta Air Lines Inc.; UAL Corp.'s United Airlines; US Airways Group Inc.; Northwest Airlines Corp. and many foreign carriers.
Southwest Airlines Co., which operates 144 daily flights from Hobby Airport, one of its busiest operations, canceled flights there and at Corpus Christi and Harlingen for Friday and Saturday.
JetBlue Airways Corp., AirTran Airways' parent AirTran Holdings Inc., Delta and AMR also operate at Hobby.
Airport spokeswoman Marlene McClinton said JetBlue and AirTran would operate until 3:30 p.m. but other carriers at Hobby would stop flying at 9 a.m.
Most airlines said that travelers with itineraries including cities in the storm's path could change plans without penalty, although exact terms could differ by carrier.