Record Hailstorms and Hailstones in the U.S.

On March 19, a severe thunderstorm pummeled Walter, Alabama, with hailstones up to 5.38” in diameter, the largest such ever reported in the state’s history and now sanctified as such by the State Climate Extremes Committee. Here is a recap of the costliest and deadliest hailstorms in U.S. history, along with a summary of the largest hailstones yet observed.

Costliest hailstorms

There have been a handful of hailstorms that resulted in $1 billion or more in damages in the U.S. The costliest storm appears to be that of April 10, 2001, which cut a swath along the I-70 corridor from eastern Kansas to southwestern Illinois and pounded the St. Louis area. Property damage was in excess of $2.5 billion in 2018 dollars.

Figure 1.  A map illustrating the hail swath and other severe weather that swept across Missouri on April 10, 2001, resulting in what may be the costliest hail event in U.S. history, now estimated at $2.5 billion (2018 dollars). A full analysis of this storm may be seen here. Map from NWS-St. Louis.

The St. Louis area was once again pounded by a series of hailstorms on April 26, 2012, causing $1.6 billion in property damage. A hailstorm that struck the Dallas/Ft. Worth, Texas metro area on May 5, 1995 caused an estimated $2 billion in damage (2018 dollars) and the same area was hit again by a destructive hailstorm on March 23, 2016 resulting in $2.2 billion in damage.

Other $1 billion+ hailstorms include three events that pummeled the Front Range of Colorado. One event occurred between Colorado Springs and Fort Collins on July 11, 1990, causing $1.6 billion damage (2018 dollars); another that affected the Denver metropolitan area on May 8, 2017, causing an estimated $2.0 billion in damage; and a third on July 7, 2009, in Jefferson County that caused $1.2 billion in damage. San Antonio, Texas experienced a hailstorm on April 16, 2016 that resulted in $1.4 billion in damage, with hailstones the size of grapefruits. It should be noted that in some of the above cases high winds also contributed to the damage totals and are not necessarily separated from the actual hail damage costs.

Deadliest U.S. hailstorms

In spite of the enormous crop and property damage that hailstorms cause, only three people are known to have been killed by falling hailstones in modern U.S. history: a farmer caught in his field near Lubbock, Texas on May 13, 1930; a baby struck by large hail in Fort Collins, Colorado, on July 31, 1979; and a boater on Lake Worth, Texas, on March 29, 2000.

Largest U.S. hailstones

The largest officially recognized hailstone on record to have been ‘captured’ in the U.S. was that which fell near Vivian, South Dakota on July 23, 2010. It measured 8.0” in diameter and 18.5” in circumference and weighed in at 1.9375 pounds. Lee Scott, who collected the monster stone, said that he had originally planned to make daiquiris out of the hail, but fortunately thought better and placed it in a freezer before turning it over to the National Weather Service for certification. The hailstone ended up at the National Center for Atmospheric Research (see Figure 2).

Figure 2. NCAR scientist Charles Knight prepares to make a three-dimensional model of a hailstone that fell in the yard of Lee Scott of Vivian, South Dakota, on July 23, 2010. The National Weather Service had this to say about the stone: “The reported value has been evaluated by the National Climate Extremes Committee and found to be accurate. This hailstone is the heaviest and greatest diameter stone on record for the United States. When initially collected after the storm, the stone had a reported diameter of 11 inches, but deteriorated in the observer's freezer owing to a loss of power after the storm”. Image credit: UCAR.

Other instances of 8-inch-diameter hail have been reported in the past but not certified. The U.S. Weather Bureau’s Climatological Data by Sections Vol. 22, Part 2 (April-June 1935) mentions a hailstorm producing 8-inch-diameter hailstones near Ponca City, Oklahoma, on April 17, 1935 (see p. 18 in the Oklahoma section). A report published in the New York Times on December 27, 1892 (apparently initially printed in the Galveston News) claimed hail of 8” in diameter fell at Gay Hill, Texas, during a storm on December 6, 1892.

Figure 3. A copy of the report of 8” hail published in the New York Times on December 27, 1892, several weeks after the event occurred in Gay Hill, Texas. From The New York Times.

More recently, what would have been the largest hailstone in U.S. history if not for the Vivian event was  a 7.75”-diameter hailstone collected in Wichita, Kansas, following a storm on September 15, 2010. Note that this happened less than two months after the Vivian event!

Figure 4. The “monster stone of Wichita,” some 7.75” in diameter and collected at the corner of Pawnee and 119th St. on September 15, 2010. If not for the Vivian event two months earlier, this stone would have gone down as the largest ever measured (by diameter) in U.S. records. Image credit: NWS/Wichita.

Below is a list by state of the largest hailstones ever measured for each state. Only a few states maintain an ‘official’ list of such records, which I have noted first in the table and then followed with a list of ‘unofficial’ sizes by state. I have gathered these reports from various sources. If any readers could add to this list or correct it, it would be much appreciated!

Figure 5. State-by-state table of official and unofficial records for largest hailstone.

Hail accumulations

Some hailstorms train over the same area (as stationary or slow-moving thunderstorms develop), producing massive hail accumulations. Hail accumulated 18” deep on level in Seldon, Kansas on June 3, 1959, perhaps the greatest on-level hail accumulation on record in the U.S.

Figure 6. An aerial view of a swath of deep hail that accumulated over Seldon, Kansas, due to 18” of hail that fell on the town on June 3, 1959. Photo from the Norton Telegram newspaper archives, Norton, Kansas.

Heavy rainfall during or following a hailstorm can cause hail accumulations to wash into ditches, creek beds, or other low-lying areas resulting in enormous piles of hail often several feet deep. This was the case during a storm south of Clayton, New Mexico on August 13, 2004 when a 12” hail accumulation was swept into a draw by 5” of rainfall. A culvert in the draw became clogged by the flow and the hail piled up to an astonishing 15 feet deep behind it!

Figure 7. Hail cliffs 15-feet high line the bottom of a creek near Clayton, New Mexico, following a deluge on August 13, 2004. The drifts took weeks to finally melt away. Photo by Barbara Podzemny.

A total of 12 people died when a massive thunderstorm produced flash flooding in Cheyenne, Wyoming, on August 1, 1985. Hail drifts up to 8 feet deep were reported, burying some vehicles. The video embedded below, from a KUSA/Denver news report, shows highway crews and residents shoveling some of the huge volumes of hail.

Some notes on large hail around the world

Bangladesh and India

The deadliest hailstorms, and perhaps the largest hailstones in the world, occur on the Deccan Plateau of northern India and in the interior regions of Bangladesh. The heaviest authenticated hailstone ever measured was one of 2.25 pounds that fell in the Gopalanj district of Bangladesh on April 14, 1986. The stone’s size was not measured, although anecdotal reports claimed the stones were the size of “pumpkins”. Ninety-two people perished as a result of the storm, though how many of these can be attributed to the hail is uncertain.

A hailstorm in the Moradabad and Beheri districts of India killed 246 people on April 30, 1888. A 2017 paper in the journal Weather, Climate, and Society notes that this is the highest hailstorm-related mortality accepted by the World Meteorological Organization.

China

In China, 25 people were killed by hail in Henan Province on July 19, 2002, and a possibly accurate report claims 200 were killed by hail in Hunan Province on June 19, 1932.

Europe

In Europe a hailstone weighing 2.14 pounds was reported following a storm in Strasbourg, France, on August 11, 1958. The diameter was not noted.

Europe’s most catastrophic hailstorm in modern history was that which struck Munich, Germany on July 12, 1984. Some 70,000 homes and 200,000 automobiles (and 150 aircraft!) were damaged and 400 people injured by hail the size of baseballs. Property damage was estimated at over US $2 billion at the time, making this a candidate for the costliest hailstorm in modern world history (see note below).

Australia

Perhaps the single costliest hailstorm in world history was that which struck the Sydney, Australia area on April 14, 1999. Hailstones up to 3.5” in diameter fell for almost 60 minutes, damaging 20,000 structures and 40,000 vehicles. The total damage came to US $4.29 billion in inflation-adjusted dollars (as of 2017).

Canada

Canada’s largest hailstone of record was that collected at Cedoux, Saskatchewan, on August 27, 1973. It measured 114 mm in diameter (4.5”) and weighed 290 grams (10.2 ounces).

What is probably Canada’s costliest hailstorm was the one which affected 130 sq. kilometers in the Calgary, Alberta, area on September 7, 1991. It caused $400 million in Canadian dollars damage (unadjusted).

Argentina

The pampas (plains) of Argentina are renowned for their severe weather. An amazing hailstorm pummeled Cordoba on February 8, 2018, with one specimen measuring 18 centimeters (7.1”) in diameter.

Figure 8. A photograph of an 18-centimeter diameter hail stone (7.1”) that was collected following a storm that struck Cordoba, Argentina, on February 8, 2018. This may be the largest measured stone on record for the Southern Hemisphere. The event was captured on video and is likely the only time such large hail has actually been filmed while falling. See the clip embedded below:

About at 08/02/2018 4 pm . Look at this video. Location Carlos Paz, Cordoba, Argentina @MatthewCappucci @RT_Digital @RELAMPAGO2018 pic.twitter.com/1n2RGXiuLb

— Granizo Cordoba (@granizoCordoba) February 9, 2018

Unsubstantiated and/or apocryphal hailstones

There are many unverified stories of giant hailstones from various corners of the world, including reports of a stone weighing 4.18 pounds in Kazakhstan in 1959; an 11-pound stone in Guangxi Province, China in 1986; and, best of all, a hailstone the size of an “elephant” in Seringapatam, India, sometime in the late 18th century! Many of these events are more likely hailstones that have fused together while melting on the ground, or perhaps megacryometeors, mysterious large chunks of ice that fall from the sky from some unknown source for unknown reasons.

REFERENCES: The only book I am aware of that is solely devoted to hail is Snowden D. Flora’s classic Hailstorms of the United States, published by the Univ. of Oklahoma Press back in 1956. It is still a great reference.

Christopher C. Burt
Weather Historian