While looking for the Mourning Warbler found by Jay Wherley at Beaver Lake, Clifton Avery and I spotted an Olive-sided Flycatcher alongside the filter pond just before 2 PM. We got good but brief looks at this larger, stocky flycatcher with dark, olive streaks on the flanks, as well as the large head and bill longer and heftier than that of a pewee. The bird also called a few times, the typical 'pit pit pit' - a nice surprise addition to the day's excitement for sure! We lost track of it while trying to get eyes on the Mourning in a flurry of activity, and efforts to relocate it were unsuccessful.
We did both see the Mourning Warbler as well, also around the filter pond. Hard to say which is the better bird for Buncombe Co. as both are considered rare migrants through the region!
Also of note - earlier this morning Simon Thompson and I had a nice male Wilson's Warbler at Hominy Creek Trail near Carrier Park. Although not rare, it's always a treat to see one and is worth mentioning.