PONTE VEDRA BEACH, Fla. – The storm Sunday in St. Johns County was so strong it looked like an atomic cloud.
This amazing vantage point taken by a drone looks south at the back of a mature thunderstorm that rattled Ponte Vedra Beach, knocking out power and driving winds to tropical storm force.
The photographer, Eric Prosswimmer, captured the rain shaft dropping out of a classic air-mass thunderstorm as it moved south at 20 mph.
It developed along the late day sea breeze after outflow from another Georgia storm propagated southward into Duval County.
That gust front, or leading edge of the outflow boundary, combined with the sea breeze to intensify the updraft.
It set off an amazing light show lasting after sunset when it grew taller and intensified into a severe storm blowing 49 mph winds into Palencia Elementary School.
Very tall thunderstorms make excessive lightning.
Radar echoes measure the height of storms and when radar returns grow to 45,000 feet, or 8.5 miles, storms typically produce more than 10 lightning flashes per minute.