A giant storm cloud can be seen in the sky above swimmers near Mollymook Beach, south of Sydney, March 5, 2014. (Photo by David Gray/Reuters)

Lightning strikes during a storm over the promenade of Palma de Mallorca, Balearics, Spain, on November 4, 2017. Mallorca and Menorca were in yellow alert because of heavy rain and violent winds. (Photo by Cati Cladera/EPA/EFE)

A migrant carries his belongings as he arrives at the Beijing railway station to catch a train in Beijing, Friday, February 13, 2015. (Photo by Andy Wong/AP Photo)

A street cleaner demonstrates his martial arts skills in front of a closed shop near Beijing's Tiananmen Square September 2, 2015 as the capital prepares for tomorrow's parade. (Photo by Damir Sagolj/Reuters)

Dog Xiaoniu dressed in clothes walks across a street with its owner (not pictured) in Shanghai, December 19, 2014. According to local media, Xiaoniu accompanies its owner to the food market everyday and is able to walk with its hind legs for up to about an hour. (Photo by Reuters/Stringer)

Aerobatic aircrafts fly during a performance at the Airshow Zhengzhou 2017 in Zhengzhou, capital of central China's Henan Province on April 27, 2017. The 5-day air show kicked off in Zhengzhou on Thursday, aiming to build a general aviation gathering center for business and communications. (Photo by Li An/Xinhua via ZUMA Wire)

A street performer dressed up as a waiter performs for at Marques de Larios street in downtown Malaga, Spain, July 4, 2016. (Photo by Jon Nazca/Reuters)

A resident walks past big waves spilling over a wall onto a coastal road in the city of Legaspi in Albay province, south of Manila on December 14, 2015, as typhoon Melor approaches the city. More than 700,000 people fled the central Philippines amid threats of giant waves, floods and landslides as powerful Typhoon Melor approached the archipelago nation, officials said December 14. (Photo by Charism Sayat/AFP Photo)