Over Spokane a few days ago, there appeared a strange formation in the sky...
A fallstreak hole or "hole punch" cloud is where... aw, let Wikipedia tell you:
Quote:
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...is a large circular or elliptical gap that can appear in cirrocumulus or altocumulus clouds. Such holes are formed when the water temperature in the clouds is below freezing but the water has not frozen yet due to the lack of ice nucleation particles (see supercooled water). When ice crystals do form it will set off a domino effect, due to the Bergeron process, causing the water droplets around the crystals to evaporate: this leaves a large, often circular, hole in the cloud.
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This also happened in Western Canada and was marvelously photogenic, so everyone went out and took pictures of it.
By nightfall, the light caused the cloud-below-clouds formation to cast shadows ABOVE itself, which must have freaked everyone out.
