“A system outage has caused us to hold departing flights. Flights in the air are not affected by this. All hands on deck to resolve,” airline officials said on Twitter.
At issue was an internal system used to dispatch flights, airline officials said.
The issue is mostly impacting West Coast flights, according to their Twitter account.
The system went down about 8 p.m. PST.
As of 9:45 p.m. Southwest was calling planes awaiting departure back to the gate to deplane passengers.
The airline gave no estimate on when the system would be fixed.