Beam of darkness

It looked as though someone was using a searchlight on our eastern horizon except the beam was dark rather than light. I've written about anticrepuscular rays previously although when you see them from the mountain they're usually spread across the sky and converge to the antisolar point. Sometimes they look a little different though. We've had a stubborn cloud just off the summit to the west that blocks the view of the setting sun, but it also affects the shadow of the mountain in the east. I think this cloud is also responsible for this ray of darkness in the sky. Meanwhile the earth's shadow, that dark band on the horizon, was as well-defined as I've ever seen.

For added strangeness, it snowed at the summit today. It was only a flurry and the snow has melted already, but snow in the middle of August? This has certainly been an unusual year for weather on Mauna Kea.