Is NYC upsetting my orchid or am I?

[bigroth]

I recently moved from the west coast to NYC and brought a few of my orchids with me. This is an oncidium hybrid...It's been humid and hot here, but I hadn't watered in a while...So I watered on arrival and then the aerial roots were looking pretty dry so I watered 3-4 days later.
Now the exposed roots are hallowing and drying up. Did I overwater? It was next to a window and getting more light than usual too. See attached picture... Ok maybe a little air from the cooler too, but the ones not next to the cooler that I watered less than a week apart are also with hallowing roots I usually water all my orchids 1x per week in CA and they like that...