A line of thunderclouds was marching past the Al Qassim region of central Saudi Arabia when an astronaut on the International Space Station shot this oblique photograph. These storm clouds made their way south and were likely related to heavy rainfall and deadly flooding in Yemen on April 13-14, 2016.

Thick dust obscures part of the Arabian Desert from our view - a frequent impediment to clear photos of the region. Some of the dark features are rock outcrops, which can rise up to 300 meters (1000 feet) above the surrounding desert floor. The gradual fade from blue to black above the clouds marks the transition from the Earth's atmosphere to space.

Dark, vegetated patches that stand out from the orange desert sand are pivot irrigation agricultural fields on the high eastern plateau of the Ad Dahna Desert. Saudi Arabian farmers produce grains, fruits, and vegetables in the middle of the desert. Agriculture has been sustained here in recent decades through water pumping from underground aquifers. This water is considered a non-renewable resource because the region's scant rainfall is not sufficient to recharge the aquifers to meet the demand. No permanently flowing rivers exist in Saudi Arabia.