Sulphurs in southeast PA

Steve Cain wrote:
The sulphurs are out in force on the Delaware. Not that I got to take
advantage of that information.


No local information here, but I do have an observation that might be
relevant:

The Sulfur hatches we have in the west usually start
late in afternoon or evening. Are these the same mayflies?
Or is it just a name collision?

Our Sulfurs are tiny #18 - #22 mayflies that are a little
browner (but not much) than the slightly larger and yellower
Pale Morning Duns. The pmds hatch at midday, and those
duns tend to ride the surface for long distances before flying
off. So trout often take the floating pmd adults. IE pmd hatches
mean good dry fly fishing.

But western Sulfur duns fly the moment they pop up out of the
surface tension. Not surprisingly, the dry fly fishing is tough.
If you want to catch fish during the Sulfur hatch, in Montana,
you're better off fishing nymphs or half-sunken emergers.

Does that fit the Delaware pattern too?