I just heard from Steve Dougill that he’s found a Northern Parula in the willows at Blacks Creek – likely a female.  He said it was calling a decent amount but not singing.  They entered from the parking area on the E side of the reserve and walked in along the N edge of the willows – the bird was mostly about 50 yards from the western edge of the willows.
Good luck to anyone who seeks it (& keep in mind its supposed to get breezy later 🙂
Jay

This trailhead is off of Rocky Canyon Road in Boise.

Approximately quarter mile up trailhead singing from top of tree. Observed
for 15 minutes, was still singing away as we continued on. Half hour ago.
Danette Henderson
Boise