From the meadow the Palisades were barely in view. We started hiking and instead of taking the glacier trail we used a steep shortcut on the west side of the meadow. This brought us to Sam Mack Lake, and we continued up towards the Palisade glacier. At one point we decided to hike up the ridge rather than stay low (this would have caused us to lose elevation and then regain it). After doing this Mt. Gayley and the lake at the base of the glacier came into view. Finally we neared the beginning of the Underhill Couloir. In order to reach it we had to get up a small section of moderately steep, compact snow. This was no problem for John with this crampons and ice axe, but I had left mine in Santa Rosa for the summer. I carefully made my way up kicking in footsteps as I went. Finally we got back onto rock and began the ascent of the couloir. We were fortunate that there was not much snow and ice present this late in the season. The couloir itself is fairly long. It felt mostly 3rd class but there were some moves that I would consider 4th class sprinkled in occasionally. Nothing too bad. We made note of several rappel stations we passed. After reaching the col at the top we began to climb and subsequently traverse the ridge towards to the summit block. Again a lot of 3rd class with 4th class moves sprinkled in. This culminated with an airy hand traverse to reach the summit block.
We had read about the rope techniques people use to ascend the block. It seemed simple enough, but unfortunately it was soon apparent that neither John nor myself are naturally gifted lasso artists. John somehow managed to get the rope caught on a hanger-less 1/4 in. bolt on the block. I decided to take a little risk and simply use the rope as aid as I climbed the 5.9 face. John was tied in (as was I) and was ready to jump off the other side of the block should the rope slip off the bolt and I fall. Fortunately such a maneuver was not necessary. I reached the bolts on top and anchored in before bringing John up on belay. We spent a few minutes on the summit and then began the trek back down.
We retreated the same way we had ascended, and made use of 4 or 5 different rappel stations to bypass as much 4th class terrain as possible. The biggest struggle for me was descending the steep snow above several small crevasses at the base of the couloir. I had a few sketchy, slippery moments but with the help of John's ice axe we both made it down without any catastrophes. As we neared the large talus ridge we met a few other guys (one from New Zealand, one local) who had done some ice climbing on the way up to North Palisade. They hadn't summited, but it sounded like a pretty good adventure anyway. Their camp was at the lake at the base of the Palisade glacier so we soon parted ways. John and I decided to take the glacier trail back to Sam Mack Meadow to avoid sketchy terrain as it was starting to get dark. This part of the descent was uneventful but LONG. Finally we made it back to camp just as the last bits of sun were starting to dissipate. We'd had a full 12 hour day and were both totally exhausted. Mountain House dinners were a fine reward for our efforts that night.
The next morning we took our time eating breakfast and packing up. We hit the trail out at about 10 am. We were back at the car at around 1:30 pm. This was an exhausting weekend, but a very exciting one as well. Thunderbolt was my first 14er, and it was certainly one of the hardest peaks I've climbed up to this point.