Lightning streaks across the sky as lava flows from a volcano in Eyjafjallajokul April 17, 2010. (Photo by Lucas Jackson/Reuters)

A combination photo shows Fata Kovacevic reacting near her flood-damaged house during floods May 20, 2014 (top) and the same place after floods October 8, 2014 in Topcic Polje. (Photo by Dado Ruvic/Reuters)

A worker sweeps leaves below a historic spirit still at Suntory Holdings' Yamazaki Distillery in Shimamoto town, Osaka prefecture, near Kyoto, December 1, 2014. Nestled at the foot of wooded hills near the ancient Japanese capital of Kyoto, the Yamazaki whisky distillery feels a long way from the northerly glens of Scotch's spiritual home. Despite its unlikely birthplace, last month Yamazaki's Single Malt Sherry Cask 2013 trumped more than a thousand challengers to be named the world's best whisky by leading critic Jim Murray in his Whisky Bible 2015. (Photo by Thomas Peter/Reuters)

Hemispheric color differences on Saturn's moon Rhea are apparent in this false-color view from NASA's Cassini spacecraft in this March 2, 2010 file photo. (Photo by Reuters/NASA/JPL/SSI)

People look at a man, who residents said was killed by al Qaeda militants, hanging on a bridge in Yemen's southeastern city of Mukalla June 17, 2015. Al Qaeda militants in Yemen killed two alleged Saudi spies, residents said, accusing them of planting tracking devices which enabled the assassination of the group's leader in a suspected U.S. drone strike. (Photo by Reuters/Stringer)

A U.S. Army soldier with the 10th Special Forces Group and his military working dog jump off the ramp of a CH-47 Chinook helicopter from the 160th Special Operations Aviation Regiment during water training over the Gulf of Mexico as part of exercise Emerald Warrior 2011 on March 1, 2011. (Photo by Tech. Sgt. Manuel J. Martinez/U.S. Air Force)

Justin Nelzen, in red vest, joins others as they work to rescue up to 70 horses along Cypresswood Drive near Humble along Cypress Creek, Monday, April 18, 2016, in Houston. More than a foot of rain fell Monday in parts of Houston, submerging scores of subdivisions and several major interstate highways, forcing the closure of schools and knocking out power to thousands of residents who were urged to shelter in place. (Photo by Mark Mulligan/Houston Chronicle via AP Photo)

The sun rises beside St Mary's Lighthouse in Whitley Bay, Tyne and Wear, as the unseasonably cool weather continues on Thursday, April 28, 2016. (Photo by Owen Humphreys/PA Wire)