We have had below normal rainfall and the barometer has been fairly stable over the last month. It's not just the rain itself that gets fish moving, it's barometric pressure. When a storm front moves in bringing rain, the barometric pressure falls and the fish migrate. Doesn't have to rain to get them moving, just as long as rain is on the way. I've seen rivers that are void of fish get huge pushes before the rains hit a day or two later. There was no rain for the fish to "smell" so why did they push upriver when the river was still considered low? Here's why:

Salmon and steelhead are extremely sensitive to changes in barometric pressure and base their migration timing on it. Just remember that when the pressure drops considerably, clouds move in and bring rain. When the pressure rises, weather gets nicer, rivers drop and fish that are present get more aggressive. Just my .02 and watch the barometer because when it drops....it's playtime!