Dark sphere crossed highway ahead of me, turned right and quickly disappeared

I am a 67-year old woman residing in Kailua Kona, Hawaii. This morning at roughly 10:20 AM (give or take a couple of minutes), I was stopped at a traffic light on Hawaii 19 at the intersection of Kealakehe Parkway. It was a clear day, blue sky all around.
Waiting for the light to change, just looking out the car window, I saw a dark-colored sphere in the sky moving quickly from East to West. My initial impression was that it was not a plane, wrong size/shape. Then I thought of drones, but it was moving way too fast to be a drone.
The sphere passed across the highway and then turned right, heading North. It suddenly shrank from view, reduced to a pin-point size and very quickly disappeared. I have never seen a plane or other flying object disappear so very quickly.
Here in Kona, I live at an elevation of 1,500 feet above Kona International Airport, so I’m very familiar with seeing all sorts of commercial planes, military planes, private planes and helicopters. This resembled none of those.
Also, in this area we never see aircraft flying east to west, as Mount Hualalai rises 8,00 feet from the ocean to the east.
I would estimate the total time from noticing it until it disappeared was 3 seconds, at most 4 seconds. Most of that time was the initial movement I saw, from East to West, before it turned north and rapidly disappeared.