This is obviously late (just now getting around to this) and so it wonít help others with conditions but there might be some tidbits of advice herein. Short Story: We made it but it was challenging, partly due to some poor decisions on our part.
My son and I (22 and 52) landed in Las Vegas on Friday, July 14th and drove directly to Lone Pine to attempt a Day Hike of Mt. Whitney (Potentially Mistake #1, perhaps should have done it in two days but hey, I didnít have time for that). We drove up to WPS to see what we were getting into, checked out the Old Trail in the daylight, headed back to Lone Pine, got some dinner and relaxed (nervously and anxiously). We then headed back up to WPS around midnight and headed up the Old Trail shortly thereafter. (Mistake #2: No acclimatization.)
We headed up the Old Trail to avoid the first stream crossing and felt good. There were a couple of streams that were difficult. We took our shoes and socks off because I did not want to hike with wet socks. We were feeling good and making good pace but were not always confident that we were on the trail due to the snow. Regardless, we felt good and were confident.
We eventually came out near Outpost Camp and were confused as to where the trail was. There was still a lot of snow and hikers randomly scattered ahead of us. We were told to head straight, and that Constellation Lake would be on our left and we should bear right then. We put on our micro spikes and headed off. This seemed like good advice to us until we saw headlamps bouncing along the trail to our right. We had completely circumvented Trail Camp (didnít know this until the descent). (Mistake #3, but not a major one.) We hit the switchbacks and things got really hard. Fatigue and altitude began to weigh on us. Most of the switchbacks were still snow covered making it more difficult. My son was struggling as I believe the altitude was impacting him. I was contemplating if I should ask if he wanted to turn around, encourage him to turn around or let him decide on his own. I was struggling myself so I probably could have turned back. He plugged along. We took plenty of rest stops and were taking our time but we made it to Trail Crest. Certainly not record time but we made it.
The slight descent after Trail Crest gave us a much needed breather. After the trip, my son confided that he may have turned back had we not had that breather. We plugged along at a slow pace. Water was running low as we did not refill when we could have. (Mistake #4: I thought we needed 3 liters but we needed 3 liters above Trail Camp.) I thought the terrain was difficult and made more difficult by the slight detour as we approached the summit. We were told to avoid the snow covered part of the trail since many were post holing there. Anyway, we made it. We were exhausted but made it. We rested for about a half hour and then headed back down. Our lack of water made it difficult but we were able to refill once we got below Trail Crest.
So, we summited, did it in one day, added a few degrees of difficulty due to ignorance but we felt like we achieved. I was particularly proud of my son. I could tell he was struggling but he pushed through. It was a real character builder and a true show of perseverance.
I would do it again but: I would acclimatize the night before, do it over two days and bring more water.
Thanks to all on this forum that helped us prepare. You are all great.