In WA, under state law, it is not a criminal law violation to merely be naked. Someone must object to the nakedness, and the naked person must be doing something bad.

RCW 9A.88.010 (Indecent exposure) provides: “(1) A person is guilty of indecent exposure if he or she intentionally makes any open and obscene exposure of his or her person or the person of another knowing that such conduct is likely to cause reasonable affront or alarm. The act of breastfeeding or expressing breast milk is not indecent exposure.”

The city or county may have more restrictive ordinance.

If you are the only one seeing the neighbor and you do not object, the neighbor should not face any legal trouble.

Even if someone objects, if all the neighbor is doing is yard work, there should not be a legal case against the neighbor

In cases like the parade, because it’s expected it does not fall under the offensive part of the law.