jd from gkc on 6/7/2011 8:40:02 PM:
Keep in mind the trailheads along that stretch don't have water. You'll need to stock-up first or stop at the bar-grills in Rhineland, Portland, Steedman, or Mokane, or at the campgrounds/B&B in Bluffton for it. Mokane also has a daytime market for bottled water.
Tebbetts (13-miles east of N Jefferson) has a hostel shelter with running water, showers, fridge, air conditioning, and roof. It's kind of a dump, but it could be a good place to cool down if need be. Its front-door key is kept outside on a utility pole. Tebbetts also has a daytime convenience store just west of town. 43-miles could be a big bite for new riders if it's hot.
Like Skyguy says, start real early the next day and ride while it's fairly cool. You can make up a lot of miles and time then. Enjoy and be careful.