In anticipation of the conditions I was out picking up “garden hackle” in the gutters and streets last night. Canned corn and paste baits work well under such conditions too. And with the falling, cold water temps associated with high flows, bait fishing is the go-to method based on creel surveys and other observational experiences. Falling temps substantially modify fish behavior.
As for high water moving the trout around, there’s no guarantee of that. Stocked trout that move do not necessarily move in association with high flows. During the stocked trout residency study the N Br Muddy Ck, York Co, was stocked under bank full, muddy water conditions and at two spots during the stocking event the stream was overflowing its banks. One could reasonably expect that under such conditions with no experience in this new environment and with no visual cues, movement would be substantial. Residency measured at the randomly selected stocking points was 90% or more when measured at least a week later.
As for wild trout, during the Spruce Ck wild BT study in 1972, following the passage of Hurricane Agnes over 70% of the trout were right back in the same locations within their territorial mosaic where they had been found prior to the flood.