Two 15 year olds see flying disk in the Hudson Valley

I am trying hard to narrow down the date of this incident. I was about 15 years old and was walking with a friend on Manitou Rd. just west of Route 9D at about midnight. We were walking with our backs to the highway and noticed the sky light up. We both turned around and saw an object in the sky, about 1000 ft. up and half a mile south of us. I saw a white, glowing disk that stood still and made no sound. After a second or two, the disk moved closer in our direction and covered a half mile almost instantly, stopping on a dime with still no sound. After another second or two, it veered off to the east, in the area of South Mountain Pass.
 I have been encouraged by books like Night Siege to think that sightings in the Hudson Valley have not been unusual.
Witness indicates that the date of the sighting is approximate.  PD