Masdevallias and humidity

[Kevinator]

So the other day, I was on the phone with Andy asking a few questions about my rootless Rossioglossum. I went ahead and asked him a few more questions about his highland masdevallias (eg veitchiana, coccinea). That was a big mistake. Now I'm pretty much hooked on to these plants as apparently they are able to withstand my warm temperatures as long as they're in porous clay pots. I seem to meet the conditions of his growing area except for one thing. I asked him about the humidity of his outdoor cool area and he said around 18 percent. But I had to take into consideration that this was due to the Santa Ana winds that we get around this time of year. The last time I tried to grow a masdevallia hybrid in these conditions resulted in leaf pleating and the death of the plant. But then again, I was using our tap water which is at around 350 ppm and it was one of the less heat tolerant hybrids. That was six years ago. Would these be able to grow in humidity from around 25-50 percent?