Ice falling from the sky in the heat of July? As alien as that idea may sound in the midst of the Dog Days of summer, it happens all the time. Hailstorms are more common during the summer than at any other time of the year, mainly because violent thunderstorms are more common during the summer.
How Does Hail Form?
Hailstones form inside massive thunderhead clouds that can tower at heights of up to 50,000 feet. While the lower regions of these storms contain warm air, the upper regions are below freezing. Updrafts within the storm system can force raindrops up into these higher regions, causing them to freeze into ice crystals. These ice particles can be pitched up and down several times causing them to partially melt and refreeze, adding layers over time, and even combining with others, until they finally become too heavy and fall to the ground.
Hailstones can range in size from smaller than a marble to larger than a bowling ball, though the average is slightly smaller than a golf ball, at about an inch and a half in diameter.
The velocity of hail varies by shape and size. The largest and heaviest can fall at speeds upwards of 110 mph.
While hailstorms can technically occur at any time of year, some of the most destructive events have coincided with the height of summer. Here’s a look at some of the worst summer hailstorms in recent memory:
- On July 30, 1979, a violent forty-minute hailstorm pummeled Fort Collins, Colorado, with hailstones as large as grapefruits. More than 2,000 homes and 2,500 automobiles were severely damaged, and falling stones injured about 25 people.
- One of only three confirmed hail-related fatalities occurred during this storm. A three-month-old infant suffered a fractured skull after being struck by a large hailstone. The child’s mother, who was carrying her, had been caught in the storm and was running to seek cover.
- The other hail related deaths involved a farmer caught in his field near Lubbock, Texas, on May 13, 1930, and a boater on Lake Worth, Texas, on March 29, 2000.
- On July 11, 1990, softball-sized hail destroyed roofs and cars in Denver, Colorado, causing $625 million in damage.
- On July 24, 1996, orange-sized hailstones caused almost $300 million worth of damage in Calgary and Winnipeg, Canada, in addition to severe flooding from the same storm system. A third of the cars damaged by the storm were irreparable.
- On July 20, 2009, a hailstorm in the western suburbs of Denver, Colorado, caused $770 million in damage.
- And on August 12, 2012, hailstones the size of golf balls battered Calgary, Alberta, Canada, for 10 minutes, causing $552 million in damage.
- On May 8, 2017, a ferocious storm blew through the west metro Denver area and hammered it with golfball- and baseball-sized hail, punching holes through cars as they traveled during the busy rush hour and blowing out windows in homes. The event ranks as the most expensive catastrophe in Colorado history, according to insurance estimates. More than 150,000 auto insurance claims and more than 50,000 homeowners insurance claims were filed. The final price tag: over $2 billion in losses.
- Severe storms hit North Texas in the early morning hours of June 6, 2018, bringing with it hail the size of baseballs that left a trail of damage from Carrollton to Arlington. Windows and skylights were shattered, car lights were cracked or smashed, and tree limbs were snapped off. Approximately 20,000 structures and 25,000 vehicles with estimated total losses of $425 million, according to the Insurance Council of Texas.
The Largest Hailstone?
The largest hailstone ever recorded fell on July 23, 2010. Lee Scott of Vivian, South Dakota, collected a monster stone measuring 7.87 inches in diameter which weighed 1.9375 pounds.
Though the Vivian hailstone is the largest confirmed one in recorded history, reports of larger stones exist. On July 27, 1910, giant hailstones fell on Minnesota’s Todd and Wadena counties. Unofficial reports claimed that one stone weighed five pounds.
Numerous other unsubstantiated claims exist. A hailstone weighing 4.18 pounds is said to have fallen in Kazakhstan in 1959. Residents of the Guangxi Province, in China, claim an 11-pound stone fell there in 1986. Most unbelievable, though, is an 18th Century claim from Seringapatam, India, of a hailstone the size of an elephant!