I wonder where one can park one's car for free for a few weeks (preferably >1 month) reasonably close to Seattle (SEA) airport. Let's say reasonably = less than 1h car ride.
Seattle's City's Traffic Code does not allow a vehicle to be parked on a city street for longer than 72 hours. Link to the legal text: Municipal code 11.72.440 "Parking Enforcement; Seventy-two (72) hours."-> one can park up to 72 hours unless posted otherwise.
Perhaps some jurisdiction nearby is more lenient but I'm not aware of it.
Note that the actual enforcement of the 72 hours in Seattle may vary according to the location and neighborhood climate (eg I parked a few hours at night in a public parking spot in West Seattle and the individual living near the parking spot complained: the car would have likely being towed after 72 hours or maybe even before). There's even a dedicated phone line for the Seattle Police 72-Hour Parking Limit/Abandoned Vehicles, (206) 684-8763.