It wasn't "mountain climbing" with ropes and harnesses and such, it was hiking, but I'll share my experience.

When I was 17 I went with my scout troop to Philmont, which is a huge property the Boy Scouts of America has out in New Mexico, to go backpacking. We spent about a week on the trail and did about 50 miles. The highest mountain we hiked up was Mt Phillips at 11742 ft (~3579M) which is right around the elevation most people just start to really feel the effects of lower oxygen levels. And that's my highest mountain.

It's been a while, so forgive me if I mix up some of my details, I'm also gonna start you off with some basic Philmont info and a side story that isn't really about the mountains.

When you first get to Philmont, you spend some time in Basecamp, making sure you have all the necessary gear, getting a quick rundown on how things work there, etc. And you spend the night in one of the tents they have set up already at base camp. If you've ever been to a BSA summer camp, you know what tents I'm talking about. For those unfamiliar, it's a big canvas tent on a wooden platform with 2 cots inside.

Philmont base camp isn't exactly what I'd consider the desert, at least not the stereotypical desert we all picture, but it's certainly a lot more dry and dusty than most in the US are used to if you're not from the southwest (which I am not) and it doesn't get a ton of rain.

But I could probably count the number of camping trips I've been on where I didn't get rained on at least a little bit on one hand, and Philmont was no exception. IIRC, that night at basecamp we got more rain than they had gotten in any 24hour period in the previous 10 years. (Coincidentally, the last time my troop sent a crew to Philmont, they also got poured on, and I believe it had been about 10 years prior)

I'm not sure if it just rained that hard, or if because they don't usually get that much rain the Philmont staff had gotten lazy waterproofing the tents, but almost every tent leaked that night, and the way the wind was blowing everyone on the one side of the tents got wet while their tent mate stayed dry. I ended up on the wet side, luckily I woke up pretty quick because the first few drops landed right on my face, so I packed up my sleeping bag, pulled on an extra layer of clothes and my rain gear, crawled under my cot and went back to sleep, so I managed to escape the worst of it. Lots of people had to dry out their gear the next morning before starting their trek.

It was pretty cool though, because you hear about how the desert comes alive after a good rain, and we got a good taste of that because the next day everything sure as hell was a lot greener than when we arrived. From base camp you then get on a bus to head off to where you start your trek (there's a lot of different trail options) but because of the rain, most of the road had turned to mud, so we had to get dropped off a couple miles from where we were supposed to start and slog through the mud to get there. By the end of the day though everything was bone dry.

A few days in we camp near the top of a mountain that wasn't quite as high as Mt Phillips would be. Our itinerary had us spending 2 nights at this particular spot, they had some activities set up for us to do, and we could rest up a little for the second half of our trek. There was a bit of an open field so we bust out a frisbee we brought with us, and toss it around a bit. That was probably about the best shape I've ever been in, and we weren't too beaten up by the hiking because A. we were young and healthy, and B. had plenty of training before we went. Even still, we could definitely feel ourselves getting a bit winded faster than we would otherwise because of the altitude.

Anyway onto Phillips. Our itinerary had camping basically at the top of Phillips. There would be no potable water at the top, so we decided to have our hot meal for the day (which involved boiling water) for lunch before we started up so we'd have a chance to refill and make sure we had plenty to get us through the next day.

As we got closer to the summit a thick fog rolled in. By the time we made it up, we were all damp, cold, miserable, tired, it was getting late, and we didn't even have a hot meal to look forward to. We pretty much set up camp and went right to bed.

The next day we wake up, and actually take a good look around, enjoy the views, etc. With the fog gone, we get to look down on the valleys below us and we see... clouds. It dawned on us then that it wasn't just fog we hiked and camped through, but a cloud. If a mattress salesman ever tells you "it's like sleeping on a cloud," fucking run, clouds suck.

While looking around and exploring we also found a decent little pile of snow up on top of the mountain. Now these aren't snowcapped peaks exactly, but it was definitely chillier up there than elsewhere in Philmont, and with the right altitude, and a shady nook behind some trees I guess you can keep some snow hanging around in New Mexico until late June/early July.

I have a few other cool little stories from Philmont, but that's pretty much the extent of what pertains to mountains, with a bonus side story about getting rained on.