Nutman,
Its gets started in ernest around Columbus Day. You will have days and weeks where the fish will never stop coming, kind of like the faucet is turned on. Then you will have times within the period where few fish are entering the river. However, during this time there are loads to catch they will just be holdover steelhead. The fresh fish will enter the river in good numbers through January. Then the fishing transitions to fishing for mostly winter holding fish and a few new ones. March is a weird month. The fish start to spawn and the fishing can be inconsisitant. In april the fishing gets hot again. There will be some newer fish as well as tons of dropbacks. The dropback fishing will last well into the month of May and possibly early June as it did last year.
The peaks are November and December for fresh fish and the last two weeks or April and the first two weeks of May for dropbacks.