Inside a Baseball-Size Hailstorm

National Geographic explorer and storm researcher Tim Samaras set out to document tornadoes and lightning on a trip through Oklahoma. But a destructive hailstorm with some hailstones nearly softball-size was a surprise highlight of this day in the field. Joining Samaras on this day were photographer Carl Young and National Geographic photographer Carsten Peter.
EDITOR'S NOTE: Along with his son, Paul, and storm chaser Carl Young—his longtime collaborators—National Geographic explorer and storm chaser Tim Samaras died in a tornado in El Reno, Oklahoma, on May 31, 2013. He devoted his life to unlocking the mysteries of extreme weather.