SALT an acronym for "state and local taxes." The recent tax changes now caps state and local tax deductions at $10,000. So high income retirees are limited to that figure for deducting these "SALT" payments from their federal taxes.
Washington State levies no personal income tax so their is another benefit against states like Oregon and California that have a heavy income tax. In Oregon one needs to make only a bit more than 100k with average property taxes to cap that SALT limit out. Be sure to check with your tax professional to see how the federal taxation changes will affect your personal situation, but the mass exodus from high 'SALT' states such as California, New Jersey, New York, and Connecticut is a clear indicator that it is making a difference.
Washington is already one of the best if not the absolute best high latitude state in the US in which to retire. Sun Belt states continue to out poll Washington due almost exclusively to the warm winters and not the economic advantages. Washington State has excellent weather with something for everyone, really. Well you won't find any 75 degree January days, but aside from balmy winters, we have it all.
Washington and in particular Southwest Washington, offers an amazing blend of mild weather, favorable taxation for the retired, and proximity to Oregon for the interstate economics. Playing in Oregon is not subject to sales tax, living in Washington is not subject to income tax. Best of both.
It is more than just a bit likely that thousands will again flee the 'salty' states of California and Oregon to the beautiful Evergreen State of Washington.