Thousands of flights face cancellation as the government shutdown continues.

Travelers across the country are facing risks of widespread flight delays and cancellations as the ongoing government shutdown threatens to put a massive dent in scheduled flights in the coming days and weeks.

As the shutdown stretches into its second month with no end in sight, thousands of flights across the country have already been disrupted as 13,000 air traffic controllers and 50,000 security screeners continue to work without a paycheck.

Some disruptions and delays were reported during the first day of cuts, but the outlook for the coming days is less certain as Transportation Secretary Sean Duffy has signaled flight cancellations will likely grow if the government shutdown continues.

Tips for travelers

Experts recommend checking flight schedules often to avoid being caught off guard by cancellations or delays.

Travelers should be "as proactive as possible" if flights are canceled, Scott Keyes, founder of Going, previously told USA TODAY.

Travelers are advised to call the international number as opposed to the domestic line, which could be jammed with high call volumes, Keyes said.

Many airlines also allow travelers to rebook via a mobile app.

Here's what to know about the ongoing flight disruptions:

Duffy orders escalating flight cuts

In an emergency order issued on Nov. 7, Transportation Secretary Sean Duffy and Bryan Bedford, head of the FAA, ordered escalating cuts to flight operations in response to the shutdown.

Flights were initially cut by 4%, and that number will rise to 10% in coming days, according to Duffy and Bedford. As many as 20% of all scheduled flights could be cut in the coming weeks if the shutdown continues, Duffy said.

What airports are impacted?

The disruptions will hit 40 of the country's most high-traffic airports, including the Los Angeles and Denver airports, Chicago O'Hare, and LaGuardia airports.

Airlines should "use their own discretion" to decide which flights are canceled to meet that goal, Duffy and Bedford said.

On Nov. 8, United will cut 168 flights and Southwest will cut nearly 100 flights, according to Reuters.

Duffy and individual airlines have said the disruptions will likely not affect international flights.

Why is the shutdown disrupting flights?

Thousands of federal workers have been sent home amid the government shutdown. Those whose jobs are deemed essential – including many air traffic controllers – are still at work without pay.

The FAA says, after reviewing data over the past month, that the "system is stressed," according to the emergency order. Since the shutdown began on Oct. 1, delays and "unpredictable staffing shortages" are "driving fatigue" and "risk is further increasing."

“We are seeing signs of stress in the system, so we are proactively reducing the number of flights to make sure the American people continue to fly safely,” Bedford said.

Will travelers get refunds?

Airlines are "required to issue full refunds" to travelers whose flights are canceled, but do not need to cover "secondary costs," according to the FAA.

Major airlines including United, Delta, American and Southwest have said travelers will be refunded for canceled flights or will be able to change their flights for free.

(This story was updated to add new information.)

Contributing: Jeanine Santucci, USA TODAY

This article originally appeared on USA TODAY: Flying today? Here's your guide to traveling during shutdown flight cuts.

Reporting by Cybele Mayes-Osterman, USA TODAY / USA TODAY

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