Company officials say a computer problem is causing significant delays for all Alaska Airlines flights.
Delays led to long lines of passengers at the Seattle airport where Alaska Airlines is the largest carrier according to a company spokesperson.
The problem is with a data connection and that technicians are working to fix it.
The airline has been unable to check in passengers for any flight since 7:40 a.m. Monday.
The airline was checking in passengers manually, according to an announcement at the Sea-Tac Airport terminal.
San Diego's Lindbergh Field reports the delays in the Pacific Northwest were not impacting travelers arriving or leaving San Diego via Alaska Airlines.
However, as of 3:30 p.m. the current flights list on the San Diego International Airport website shows that many Alaskan Airline flights leaving from San Diego have been delayed throughout the day.