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Goodness gracious, great balls of ice!

What the hail?

WMAR

By: Stevie Daniels

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It is Severe Storms Awareness Week in Maryland, and today we are going to explore the science behind hail and how you can stay safe!

Since hail consists of balls of ice, you may think we normally see hail in the winter time. The spring and summer seasons are when we typically see hail here in the Mid-Atlantic because hailstones form inside thunderstorm updrafts. Thunderstorms are occur more often in spring and summer! A water droplet is carried upwards by the updraft above the freezing level in the atmosphere. The water droplet collides with super-cooled water droplets that freeze on contact to the hailstone's surface...this is how hailstones grow. Super-cooled water is when the temperature of a liquid has dropped below the freezing point, but still remains in a liquid state. The hailstone will fall to the surface if the updraft weakens or if the hailstone becomes too heavy to be supported by the updraft.

Hailstones can come in all shapes and sizes! Hailstones can have layers of both clear and cloudy-looking ice. The appearance of hailstones depends on how quickly the water freezes to the hailstone. The layers on a hailstone are determined by the liquid water content and temperature within a thunderstorm.
Hail sizes are estimated by comparing it to a commonly known object. Smaller hail (less than 1" in diameter) is usually associated with non-severe thunderstorms. Hail 1"+ is considered to be severe and usually forms within strong supercell thunderstorms.

According to the National Weather Service, the largest hailstone ever recorded was 8" in diameter and fell in Vivian, South Dakota in 2010!
The largest hailstone on record in Maryland was 4.5" in diameter in 1971 and 2002. In 1971, the 4.5"-sized hail fell in the Phoenix, Cockeysville, and Jacksonville area. In 2002, 4.5"-sized hail was recovered in Charles county.