Would be tough to pull off in WA with our short halibut seasons not really overlapping the salmon runs, but I've heard from family in AK that it's not as hard as one might think. And not by bullsh*t jigging with a fly rod either. The 'butts will move onto shallow (up to 30' or so) sandbars and banks off the river mouths to ambush schools of salmon on the incoming tide. 12 or 14 wt, extra heavy coldwater sinking line, huge horse-herring flies and 300 yards of backing. No loop to loop connections. We C & R'd two chicken halibut in around 50 ft of water off Wadda Island and south of Tatoosh last July gear fishing for kings. I'd say halibut on the fly is at least possible in WA, if not easy.