Severe Weather Week: Hail Formation

PHILADELPHIA (CBS) -- We're continuing Severe Weather Week here at CBS3 and Wednesday's topic was all about hail.

 HOW DO HAILSTONES FORM?

"Hailstones form in a strong thunderstorm with strong updrafts and down drops," says Meteorologist Kate Bilo. "So raindrops fall but then they get sucked back up into the thunderstorm in the updraft and they basically just circulate through the thunderstorm. They refreeze, they melt, they refreeze, they add dust particles and super cold water droplets and they grow in size. The stronger the updraft the larger they'll grow. When they're heavy enough, when they can't be sustained by that updraft anymore, they will fall to the ground."

DIFFERENCE BETWEEN SLEET AND HAIL

"It's a completely different process," Bilo says.

Sleet: Snow melts in a warm layer then refreezes and falls to the ground as ice pellets.

Hail: Droplets circulates in updrafts, freezing in cold air aloft before falling to the ground.

CLICK HERE to learn more about Severe Weather Week.