Post a link to this message on the "Name that Plant" forum. Looks somewhat like Celandine Poppy, but not enough for me to be confident in saying so.

Here is a link that might be useful: Name that plant

I second that opinion -
only I don't know which it is
celandine (wood poppy) native (stylophorum)
or alien celandine (chelidonium)....
the native has larger flowers.
if/when you see the seed pods, it'll be easier to tell which.
The native has hairy oval dangly pods (pardon my lack of proper terminology), and the other has thinner ercct seed pods.

did you really mean feet tall? celadine poppy is only listed as 12-18 inches.

does it get woody or turn red in the fall?

I have it. It is Plume Poppy.
I guess it can get up to 8' and be very invasive if happy.
Mine only reaches 5'-6' and is spreading slowly.
I love it.

Thanks everyone.