Mr McGowan extended the 24-hour deadline for these people to be tested as lines outside COVID-19 clinics grew long on Friday.
Since the 3pm announcement on Thursday, 1936 people have been tested in WA, including 522 at the airport upon their arrival; a 172 per cent jump from the previous day.
Those people are now in self-quarantine awaiting their results.
“This has been a fast-evolving situation,” Mr McGowan said.
He said he understood the changes to border arrangements had thrown Christmas plans into disarray for many people.
“This is a deadly global pandemic, we cannot forget that,” he said.
Prime Minister Scott Morrison said there was hope for Christmas travel.
“The sooner we’re able to move through these decisions over the next few days, I believe the sooner we’ll get to a point, I hope, that the early concerns we hope may be alleviated, but it’s still too early to say,” he said.
“There is no magic formula that makes the pandemic just go away.”