I drive a wine-tour van and was parked at 45 North Vineyard, awaiting a tour group. Seated in the shade, I was observing a small flock of birds hovering in search of food in the vineyard. Noticed a brown object among the birds that was circular and totally still. It struck me, so I stood up and that's when I felt a strange feeling that the object "noticed" me. Just as I began to realize I was seeing something unusual, the object quickly zig-zagged and then headed due west at a high rate of speed (into the wind) and behind the building. I thought, "Wow, I just saw a UFO and it's just like everybody else says - It hovered, moved quickly and without a sound, and then disappeared."