Only down to the 50's? You must not be at that high an elevation Thistle. We used to camp in Hog Park Wyoming, just across the Colorado line, at elevation 8400 feet in August. There would be ice in the water bucket in the morning. You didn't get out of your sleeping bag until 7:00 and the second thing you did was get the fire going. Yet by 9:00 or 9:30 you'd probably be OK in a long sleeved shirt, light jacket at the most. Then a mile and a half hike into fun trout fishing. They were small, 11" was a good fish, but it was so isolated they were wild enough even a rookie fly fisher like me could catch some. And the kids even caught a few. Of course, most of my time was spent retying flies for the boys.