SUNDAY'S UPDATE TO THIS STORY CAN BE FOUND HERE: Harvey cancellations soar to 3,000; All Houston Hobby flights grounded Sunday

Last update: Saturday, 8:30 p.m. ET

Flight cancellations soared Saturday as Hurricane Harvey’s effects were felt at airports across large parts of Texas. Additionally, airlines were waiving change fees for fliers ticketed to fly to airports in the storm's path.

More than 1,060 flights were canceled nationwide as of 8:30 p.m. ET, according to flight-tracking service FlightAware. The bulk of that total came in Texas, where many of those cancellations were made preemptively even before Harvey made landfall. An additional 1,115 flights had been preemptively grounded for Sunday while another 360 have already come off the books for Monday.

That follows roughly another 200 Harvey-related cancellations from Friday. Combined, nearly 2,700 flights have been canceled since Harvey began affecting flights on Friday.

On Saturday In Houston, some Saturday flights were taking off and landing at the city’s Bush Intercontinental and Hobby airports, though fliers faced mounting delays and cancellations.

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At Intercontinental airport, where United is the dominant carrier, about 725 flights had been canceled for Saturday, as of 8:30 p.m. ET. That spiked sharply since Saturday morning, when less than 100 cancellations were reported. So far, Saturday's cancellations account for a about two-thirds of the daily schedule there, according to FlightAware’s calculation. The outlook for Sunday looked even worse; more than 800 flights had already been canceled, nearly 70% of the entire day's schedule.

For Saturday, United ultimately grounded all of its United Express regional flights and canceled most of its "mainline" flights except for those flying to international destinations and to its other hubs.

“We plan to continue operating flights from Houston to our hubs and most international destinations,” United spokesman Charles Hobart said in a statement to Bloomberg News.

At Hobby – a major base for Southwest – about 130 flights had been canceled as of 8:30 p.m. ET, representing about 40% of the day’s schedule there. The number of cancellations there had roughly doubled since early Saturday morning.

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Flights at the airport in Corpus Christi had been suspended altogether since Friday afternoon. It was unclear when they might resume. The airport also took the unusual step of closing its terminal Friday evening.

At the Valley International Airport near Harlingen and South Padre Island, Southwest had suspended its entire schedule at least through late Sunday.

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Travelers heading through other airports in south and central Texas should be prepared for disruptions. In Austin and San Antonio, for example, Southwest warned its schedules at those airports were expected to see “some adjustments” on Saturday – largely the ripple effect of Harvey-related schedule changes at Houston Hobby.

As of 8:30 p.m. ET, about a quarter of the entire day's schedule had been canceled at both the Austin and San Antonio airports. About the same number of flights had also been preemptively canceled for Sunday.

Customers flying to any airport in the region during the next few days should check ahead on the status of their flights. Fliers should also consider airlines’ flexible rebooking policies to move their flights to dates after the storm.

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Even nationwide, Harvey could create sporadic disruptions. A flight from Chicago to San Francisco, for example, could become delayed or canceled if the plane or crew scheduled to fly it gets knocked off track by the problems in Texas.

However, airlines have become more aggressive in trying to prevent that scenario in recent years. That’s why it’s more common to see large blocks of preemptive cancellations these days; it’s all part of the industry’s efforts to contain weather-related ripple effects during extreme storms.

By grounding flights altogether ahead of poor weather, airlines hope to accomplish two main objectives. First, they can try to keep their aircraft and crews from becoming unexpectedly stranded if weather worsens faster than expected. Second, by having idled planes (and crews) waiting at the ready, carriers say they’re able mobilize quickly with a nearly full schedule once conditions allow flights to resume.

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