What date and do you have pre-check? Right now things are chaotic at SEA due to a cyberattack. The area that seems mostly impacted is baggage check. If your flight is a date that is once the situation is resolved, theoretically it should be enough but TSA lines at SEA can be very long, especially the non pre-check ones so I think it would still be tight. If you don't have to check a bag and just travel with a carry-on then its a breeze, don't even need to leave security. Hope this helps.