On the upper river weather determines intensity and fly-fishing success during the PM brown drake emergence. Try to use good weather evenings for best chances. Recreating boaters are coming to Box Canyon, and they have the same right to use the river as anglers. Their numbers peak during mid-day, so to minimize interference consider early AM, or late afternoons for your visit here. AM and PM spinner falls, afternoon caddis activity, PMD,and beginning-to-diminish flav activity give the best chances for success in the Last Chance-Harriman section.
PM caddis activity and the same spinner falls as on the upper river provide good fishing on the lower river. Green and gray drakes provide action, but begin fading out there as the river warms. Another bit of good news is that the South Fork stonefly hatch has transferred many boat away from this part of the river. This week will see rising air temperatures on the lower river and therefore rising water temps.