Fall is by far the best time of the year for the Yakima. Its extremely easy to wade right now and there's plenty of access. Plus, the crowds have thined out considerably.

You should first stop at one of three fly shops for a little help on what to use. Dries like October caddis are a good bet , plus BWO's and sparkle duns. Also pheasant tail nymphs and princes have been pretty effective for me. Of the fly shops, I like Red's the best, which is located by the Umtanum access area. Here's a link to their website which provides a up-to-date fishing report plus a map of the access areas. http://www.redsflyshop.com/

IMO, average size is about 12, with a good catch being about 17.

Have fun! Be prepared for a range of temperatures and conditions. It could be as cold as the high 30's or as warm as the mid 70's and rain is possible.