Mammoth hail keeps pelting parts of Central Texas.

Cantaloupe-size hail — approximately 6 inches in diameter — was recovered following rotating supercell thunderstorms earlier this week. One of the stones that fell in Menard was 5.87 inches across and was picked up by a team of researchers conducting a hail study field mission. While it just missed this threshold, the technical term for 6-inch hail is “gargantuan” (yes, really).

A year ago this week, meteorologists at the National Weather Service in Lubbock issued the first-ever “DVD-size hail” warning, corresponding to stones at least 4.75 to 5 inches in diameter.

Hail that large is difficult to detect on radar. Unless forecasters receive real-time reports from storm chasers or the public, most warnings are usually for softball-size (4 inches in diameter) or grapefruit-size (4.5 inches in diameter) hail.

Standardized lexicon

Sunday’s biggest hailstones fell in Afton — about 70 miles east-northeast of Lubbock. The storm chasers who found them estimated they weighed nearly a pound and a half each.

On April 24, storm chaser Adam Lucio posted on social media that he recovered a 5.22-inch hailstone near Cedar Hill. And on April 29, a 4.74-inch DVD-size hailstone was found during a storm in nearby Guthrie.

The vicinity of Dickens County had three DVD-size hailstorms in 33 days. And it’s roughly the same area where a 7.25-inch stone fell on June 2, 2024. (That one hit the rural settlement of Vigo Park and was approximately the size and shape of a pineapple.)

The National Weather Service has implemented a standardized lexicon for talking about big hail. “Baseball-size” hail is 2.75 inches in diameter, for example. Three-inch hail is “teacup-size,” and 3.5-inch hail is “large apple-size.” Meteorologists hadn’t really thought of anything past DVDs given the rarity of six-inch hail. Now, storm chasers have gravitated toward “cantaloupe-size.”

Why is so much of this huge hail being produced in this part of Texas?

Clashing air masses

The spring months feature something called a “dryline” in west Central Texas. That’s the border between bone-dry desert air to the west and moisture-rich Gulf air to the east. Those clashing air masses, which wage regular battles near Interstate 27 from Amarillo to Lubbock and then south to Midland-Odessa, spark rotating supercell thunderstorms that can produce massive hail.

But east of Lubbock, there’s also another factor at play — the presence of Palo Duro Canyon and the Caprock Escarpment. It’s the transition zone between the lower-elevation rolling terrain to the east and the elevated high plains of the Llano Estacado, situated at more than 3,000 feet elevation, to the west. The rocky, uneven terrain of the Caprock makes for uneven heating, with sunshine on some features and shade falling on others. That can induce local circulations and air currents that frequently generate the first storms of the day. And whichever storm sprouts first often has access to the greatest supply of undisturbed storm fuel.

The world record (and national record) is an 8-inch diameter hailstone, which was logged during an extreme storm in Vivian, S.D., on July 23, 2010. It weighed 1 pound 15 ounces and left a crater in the ground.