About 28 flights leaving from Portland International Jetport experienced “some level of impact” following Wednesday's federal order to ground all flights across the country.

Jetport Director Paul Bradbury said two early morning flights took off on schedule shortly after 5 a.m., but then everything else was grounded after that.

The stop was lifted around 9 a.m. The Federal Aviation Administration said there was “an overnight outage to the Notice to Air Missions system that provides safety info to flight crews,” according to a message posted to Twitter. “We continue to look into the cause of the initial problem.”

At the jetport, the online arrivals board posted to its website showed six canceled flights and four delayed flights at mid-afternoon. With regard to departures, three were listed as canceled and five were delayed.

Bradbury said nationwide and particularly for Portland, it’s the slowest time of year for air travel. But following days-long delays from Southwest over the holidays, it’s been a difficult time for air travelers.

“This level of ground-stop is unprecedented in my experience,” he said.

At Bangor International Airport, one incoming flight was listed as canceled and three were delayed, while one departing flight was canceled and five departures were delayed, according to the airport website.

“Really, we had less than a handful of passengers in the terminal and we only experienced a few delays,” said Aimee Thibodeau, marketing and business development manager for the airport.

Like in Portland, Bangor was able to get its early morning flights in the air before the FAA shutdown.

Thibodeau urged passengers to double-check departure times for the remainder of the day, warning that there will likely be more delays as the nationwide system gets back up and running.