Severe thunderstorms are expected to blossom across portions of the Mid Atlantic and Northeast this afternoon and evening and the National Weather Service’s Storm Prediction Center (SPC) is warning of the threat of hail from these storms. The greatest hail threat from these storms is over Delaware, much of New Jersey and Maryland, portions of Pennsylvania, Virginia, Ohio, Upstate New York, and northern New Hampshire, Vermont, and Maine.
The National Weather Service officially defines a severe thunderstorm as one capable of producing hail that is 1 inch in diameter or larger, which is about the size of a quarter. Hail smaller than 1 inch is considered non-severe or “small” hail.
Hail is a form of precipitation consisting of solid ice that forms inside thunderstorm updrafts. It’s formed when raindrops are carried upward by thunderstorm updrafts into extremely cold areas of the atmosphere and freeze. Hailstones then grow by colliding with liquid water drops that freeze onto the hailstone’s surface. If the water freezes instantaneously when colliding with the hailstone, cloudy ice will form as air bubbles will be trapped in the newly formed ice. However, if the water freezes slowly, the air bubbles can escape and the new ice will be clear. The hail falls when the thunderstorm’s updraft can no longer support the weight of the hailstone, which can occur if the stone becomes large enough or the updraft weakens…