Folks seem to think that dry fly action in the Cumberland Valley has been pretty sparse this winter. Nevertheless, with the recent warm up, you might have a shot at some early stones or BWOs. Letort would probably be your best bet for BWOs. However, if you need to travel a long distance and really have a desire to fish dries, you might care to wait awhile.
Also, note that with trout season closed and the heavy flows right now, the CV limestoners are likely to have a good number of fishermen.