Just picked up a couple of orchids at Costco. Had the orchids in a
warm area with lots of morning and noon sun through lace curtains.

Noticed that the tips of leaves are turning yellow brown--the same
kind of look that burnt leaves have. The flowers are also getting dry
and brown and are falling off.

What is causing the problem? (I suspect humidity is too low or
underwatering.) What can I do to fix it?

Thanks in advance.

Lil