Update: As of 8:40a.m. EDT, Delta has lifted the full ground stop and some flights — “limited departures” — are starting to be able to take off. However, customers flying this morning should still expect lots of delays and cancellations, Delta says, and should check in with the airline before heading to the airport if you’re not there already.

As of about 10:30 EDT, Delta reports cancelling 300 and operating 800 of approximately 6,000 flights. “While While systems are improving and flights are resuming,” the airline says, “delays and cancellations continue.”

Original post:

Happy Monday, travelers! It’s a great day for flying… unless you’ve got or are trying to make a Delta reservation, in which case you are, well, kind of up a creek without an airplane.

This morning around 5:00 a.m. EDT, Delta announced that a power outage that started around 2:30 was interfering with its computer systems.

At that point, any flights already in the air were operating normally but flights still awaiting departure — which, that early in the day, is most of them — were expected to be delayed. From that point, the issue has only cascaded.

Delta’s most recent update, as of 7:30 a.m., says “large-scale cancellations” are expected during the day. Want to know if that includes yours? Good luck finding out: part of the systems failure means that the website and airport screens are incorrectly showing flights as on-time, rather than cancelled.

“A power outage in Atlanta, which began at approximately 2:30 a.m. ET, has impacted Delta computer systems and operations worldwide, resulting in flight delays. Large-scale cancellations are expected today,” Delta said. “All flights en route are operating normally. We are aware that flight status systems, including airport screens, are incorrectly showing flights on time. We apologize to customers who are affected by this issue, and our teams are working to resolve the problem as quickly as possible.”

In a tweet at about 5:20, a Delta Air Lines rep tweeted that all flights were grounded due to the outage, so it’s probably safe to assume this morning that that means yours, too. You should, of course, check with customer service but expect high volumes through all avenues, both phone and social media, and be patient if you’re stuck in an airport with hundreds of fellow wayward travelers.

Delta has already announed free changes / travel vouchers for passengers who were supposed to get somewhere today and now can’t.

However, as we saw with Southwest’s outage last month, it can take days to get all the planes and all the passengers and crew back where they’re supposed to be after a massive technical glitch. And that was “only” around 1500 flights domestically getting grounded. Delta’s outage is likely to have significant repercussions around the world for days to come.

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