Clouds that make you go, hmmmm

Many people around the region saw this very odd cloud formation Friday. So did Shad Moore, who took this photo with his phone on top of Grand Coulee Dam and sent it to us later. Meteorologists call it a Fallstreak Hole. "Such holes are formed when the water temperature in the clouds is below freezing, but the water, in a supercooled state, has not frozen yet due to the lack of ice nucleation," states the entry in Wikipedia. "When ice crystals do form, a domino effect is set off ... causing the water droplets around the crystals to evaporate; this leaves a large, often circular, hole in the cloud. It is thought that the introduction of large numbers of tiny ice crystals into the cloud layer sets off this domino effect of fusion which creates the hole." Now if we just knew who Fallstreak is. Thanks to Rob Chamberlain for finding that term and posting it on Facebook. - Shad Moore photo