Hey there,

First, thanks to everyone for sharing all their knowledge and experiences and the people who maintain the trail. Maybe some minor detail here might prove useful to someone.

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I picked up a spontaneous day use permit a while ago from a cancellation. As the day approached the summit forecast got worse and worse, calling for 50 mph winds and 7 degree temps (f). Weather was supposed to get worse over the day peaking late day. I decided to go anyway and just make it about having some fun with trying to go fast at night.

Spoiler: the cold got to my fingers and toes by Trail Crest so I turned around.

Weather
Temps seemed as forecast, 50s at the portal going down to 30 up top with the 50mph winds taking it down to 7 degree feel.

Clothes/Pack
I left wearing a long sleeve dry fit upper under a micro windbreaker (hooded) and a running vest over both. I wore full length stretch lower base layer and gore tex running pants the whole time. I run trail distance with double wool socks (toe socks under normal socks), and mid cushion trail running shoes. In my running vest I carried a nano puff, a gore tex upper shell (hooded), a wool balaclava, a pair of heavy duty skiing gloves, emergency bivy, 2 500ml soft flasks full of water, one empty 1l soft flask with a Be Free filter, 10K battery pack, phone, gopro, headlamp, gps watch, charge cables, 8 home made energy gels (2K calories + electrolytes), 4 home made energy bars (2k calories + electrolytes), sunscreen, lip balm, soy and hot sauce packets (emergency cramp relief), wag bag, permit/rules, keys, id.

Timeline

11:00 pm - Portal
I left the portal and weighed my hydration vest on the way out for fun. 10 pounds total carry weight. Looking at distance and elevation, I figured I'd get to the Whitney permit zone at midnight.

12:00 am - Whitney Zone
I got to the Whitney permit zone sign at midnight. That worked out. I got my puff out at this point and put it on between my upper base layer and windbreaker with the vest over both. Trail was easy to read, streams were easy to cross. I felt mostly sheltered from wind before this. I passed one pair of hikers near here. Some point between here and Trail Camp further up, I put on the gloves.

01:30 am - Trail Camp
I felt like suddenly I was at Trail Camp. Moving at night is surreal, big things can change around you while you focus on small things moving beneath your feet in your light cone. Still no surprises, minor bits of ice, some rocky areas with less clear trail but plenty of placed stones visible to read the way without trouble. Stream crossings were low and easy. Wind increased with exposure. I swapped out my cap with the balaclava and put on the gore tex shell over everything including the vest. I passed a second pair of hikers near the bottom of the switchbacks who had camped at Trail Camp.

The Switchbacks
I honestly enjoyed these. I love climbing. I think this section gets a bum rap. There's a surprising amount of runnable ground and there aren't as many big steps as I'd imagined. I felt there were more large steps in other sections on the approach below. The spring was running, some spots had icy bits over them, everything was obvious, easily avoidable without spikes, and the trail was easy to follow even at night. There was a little snowy bit, also avoidable and one small 'snowfield' with a path through it. The cables were clear (felt surreal to first notice them in my peripheral vision). I really loved this entire section. I'd love to see it in the light sometime, the loft must be really impressive. I just geek out marveling at the engineering of these types of trail sections and the time flies.

03:00 am - Trail Crest
I got goose bumps when I saw the Trail Crest sign. Walking around the crest up there to the junction at 3 am completely alone was surreal. We're in new moon phase so it was pitch black darkness. Amazing stars and I could turn all my headlamp lights to full and get spooky glimpses of the granite super fortress around me. I couldn't see the headlamps of the two hikers I'd passed down at the bottom of the switchbacks anymore, and I couldn't see any headlamps down the JMT west side or going up the west slope to the peak. I might have been the only person up there. What a trip, it's just an amazing feeling knowing so much looms around you in the darkness. The wind was strong but not impossible. Some gusts would catch me off balance. The darkness helped remove any vertigo which likely made the wind feel less dangerous.

Choices
For the last half hour approaching Trail Crest my fingers and toes were getting colder to the point of not warming anymore after doing appropriate wriggling waving armpitting massaging etc. I was feeling numbness on my big toes and having grown up with real winter I know early frost bite signs and don't take risks. I knew up front my shoes wouldn't be appropriate for real summit weather if the forecasts were correct. I had hoped the gloves would be adequate (I don't own mitts, I just avoid cold things nowadays). My mentality from the beginning was that I was there on a bad weather (for me) day and I was just going to have some fun and see what happened. I had no expectations or pressure to get to the summit. Based on my time so far (4 hours to Trail Crest / Junction), I estimated at least 2 hours to summit and return to Trail Crest (then more time to descend towards Trail Camp and warmer temps). I decided it was time to move to warmer temperatures now instead of add more time and possible uncertainty.

Returning
Temps warmed up and wind dropped quickly while descending the switchbacks. I ran a lot of it, there's a surprising amount of flat. I shared what I'd experienced with the pair of hikers I'd passed earlier and wished them luck. I started to pass more hikers as I got closer to the lower camps that were starting their early hike. Like always, I wave and stop and give uphill people the right of way. There was a lot of runnable ground. I stopped once to refill my flasks on the way down only. It started getting lighter as I was approaching the Whitney Zone boundary. I was lazily still wearing all my layers even though it wasn't near as cold anymore so with my vest being under my shell I guess it looked like I had no carry. I passed a group of hikers where one called out "where's your backpack?" I thought.. but a ways down the trail I realized they most likely said "where's your wag bag?" I don't know, maybe they were angry at seeing me and assuming I had none because they saw no pack? I just don't know, that kind of thing bothers me, for all they know I have a colostomy bag (I don't). Nearer the bottom of the trail just as the sun was cresting the east valley mountains I happened across a signature Mount Whitney trail deer that stopped to share the sunrise with me. It was nice.

06:00am - Portal
I started passing many groups of hikers starting their day near the very bottom then suddenly I was back at the trailhead. What a fun night!

Takeaways
  • obvious: really amazing place, thankful to spend time there, wow
  • this makes me think maybe I could summit in 5 and get back in 4 if I ever wanted to try a fast go at it again (it's not a race, I'm just curious for me)
  • night time is good for low crowds, as is weekday, as is new moon, I wouldn't run there any other time
  • 50 mph wind and sub 10 degree temps is certainly no go threshold for me (I'm strictly fair weather nowadays)
  • 2 500ml flasks were fine for a night trip, I could start with just one full, there's so much water
  • I'd probably switch to calorie/electrolyte powder in water instead of gels for high intensity effort at high altitude
  • I always carry beyond extra calories for emergency, but I probably only needed ~1K for the time/effort
  • I don't run trail with poles and didn't need them here either
  • switching to liquid calories after noon the day before and moving my bowels in the evening before leaving is fine (I have no issue with using bio bags, but no need if you can plan around it, tmi)
  • a lot of the larger rock spots on the lower trail seem really slick from decades of foot traffic, minor but worth being mindful of


Thanks again for all the info everyone else has shared.