Commissioner Ty Votaw said the tour was following President Bush's lead 'to start to get our country back to normal so the healing can begin.'
If a national day of mourning is ordered, Votaw said the event would be reduced to 36 holes.
As it is, there will be no play on Friday, with 18 holes being played Saturday and 36 on Sunday.
Safeway spokesman Brian Dowling said: 'They've cut out the pro-am (Wednesday), and the tournament will not be played on any national day of mourng, whenever that may be. All of the proceeds go to charities in the Potland area. That's the rationale If there were no significant charity angle to this event we would not proceed. Through the years we've raised hundreds of thousands of dollars in the Portland area.'
The decision comes in the wake of terrorist attacks Tuesday in New York and Washington, D.C.
The PGA Tour has cancelled all four of its tournaments slated for this week, including the WGC-American Express Championship in St. Louis, the Tampa Bay Classic, the Buy.Com Oregon Classic and the Senior PGA Tour's Vantage Championship in North Carolina.