WestJet Airlines鈥� check-in services have been restored, after a temporary system outage caused flight delays and snarled travel across Canada Thursday morning.

WestJet spokeswoman Morgan Bell said travellers are still being encouraged to arrive early and check their flight status before heading to the airport. She said the airline is still experiencing issues with its self-serve baggage drop at Calgary, Ottawa, Saskatoon and Halifax airports.

System outages affected both WestJet Airlines and air traffic control agency NAV Canada on Thursday, with travellers on social media reporting long lines and confusion at airports.

Elle Dunlap from San Francisco, Calif. 鈥� who was travelling with her husband and five-year-old son Thursday to Saskatoon, Sask. for her husband鈥檚 brother鈥檚 memorial service 鈥� arrived at the San Francisco International Airport at 6 a.m. Thursday morning. Their flight, with a scheduled connection in Calgary, was supposed to depart at 8:30 a.m. but as of 9:15 a.m., the family was still waiting.

鈥淚 was anxious about this flight anyway because I鈥檝e heard about some of the troubles with domestic flights within Canada,鈥� Dunlap said in an interview, adding she first suspected there was a problem when the family was unable to check in online.

鈥淲e came to the airport super early, but there was just no communication (from WestJet). It was just 鈥榯he system鈥檚 not working鈥� and we were just waiting in line with 100 other people for hours.鈥�

NAV Canada, the not-for-profit corporation responsible for air traffic control in Canadian airspace, said it was experiencing disruptions in western locations Thursday due to a service outage with its third-party telecommunications provider, Zayo.

Zayo spokesperson Karen Modlin said the outage amounted to a disruption of two key fiber lines managed by one of the company鈥檚 underlying fiber providers in Canada and was caused by a train derailment Wednesday evening.

鈥淲e have rerouted a significant volume of traffic via other routes so that our customers can begin resuming normal operations,鈥� Modlin said, in an email to The Canadian Press.

鈥淲e regret the inconvenience this has caused for our customers and air passengers, and our top priority is the safety of everyone involved.鈥�

NAV Canada spokesman Brian Boudreau said air traffic control reduced the flow of departures and arrivals temporarily in some locations as a result.

He later added that services are 鈥渞eturning to normal.鈥�

The outages Thursday are exacerbating what has already been a frustrating summer for Canadian air travellers.

Airlines and airports have been struggling to cope with a massive travel resurgence in the wake of the lifting of COVID-19 restrictions, and staffing issues at carriers and federal agencies have resulted in flight cancellations, baggage delays and endless queues.

鈥擜manda Stephenson, The Canadian Press