May 15, 2014
Date of sighting: May 9, 2014
Location of sighting: Stockton, California, USA
News Source 1: http://strangesounds.org/2014/05/mystery-and-rare-fallstreak-hole-cloud-phenomenon-over-stockton-may-9-2014.html
News Source 2: http://sacramento.cbslocal.com/2014/05/10/hole-punch-cloud-spotted-in-stockton/
The sky appeared to be opening up over Stockton California as multiple photographers captured this amazing event on May 9, 2014.
This strange cloud formation in the sky of Stockton is a so-called fallstreak hole, also known as a hole punch cloud.
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. 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.
Because of their rarity and unusual appearance, fallstreak holes are often mistaken for or attributed to unidentified flying objects.
CBS13 News states:
STOCKTON (CBS13) – An unusual cloud spotted in Stockton caused a storm on social media Friday afternoon.
Photos started flooding social media a little after 2 p.m. Many people characterized the event as a UFO, using hashtags like #alien, #weird and even going so far as saying the earth was due for an extraterrestrial invasion. (more at source).
Thanks to: http://missiongalacticfreedom.wordpress.com