Hail: The Most Underrated Costly Weather Disaster
Published: July 13, 2017
It may not capture your attention, fear or fascination like a landfalling hurricane or tornado outbreak, but hail is consistently one of the most damaging weather phenomena every year.
Its annual cost to America's insurers, homeowners and farmers runs in the billions of dollars.
"Over the past few years, according to industry sources, we've seen $8-10 billion in insured and agricultural losses annually from hail alone," said Bryan Wood, meteorologist and operations analyst with Assurant, Inc.
Some of this can be attributed to the sheer number of severe thunderstorms in the U.S.
From 2010 through 2016, an average of 6,339 reports of large hail were received by National Weather Services offices each year.
Large hail is defined by the NWS as hail at least 1 inch in diameter, roughly the size of a quarter. Hail this size or larger is capable of more significant property damage.
Reports of large hail - at least 1 inch in diameter - in the U.S. in 2016.
In a few cases, a single hailstorm can be a destructive, billion-dollar event.
"If you get a significant hail swath traversing a densely-populated area at peak time of day, you're looking at a potentially catastrophic event loss," said Steve Bowen, meteorologist with Aon Benfield.
One example of this was a pair of hail events across the Omaha, Nebraska, metro area on June 30, 2017.
Hail up to the size of baseballs in Denver on May 8, 2017, was the costliest weather disaster in state history, responsible for $1.4 billion in insured losses, the Rocky Mountain Insurance Information Association estimated.
(MORE: Nine Billion-Dollar U.S. Weather Disasters in 2017 So Far)
Just over a month later, a hailstorm in the northern suburbs of Minneapolis was estimated to be responsible for almost $1 billion in damage, at least the third costliest storm in state history, according to the Insurance Federation of Minnesota.
Paced by multiple events in spring, Texas suffered record hailstorm losses in 2016.
The costliest hailstorm in U.S. history hit the Phoenix metro area on Oct. 5, 2010. An estimated $2.8 billion in damage was caused by that storm, according to NOAA's storm events database. Hailstones up to three inches in diameter were measured in the West Chandler area.
In April of 2001, a single supercell thunderstorm with hail up to three inches in diameter tracked across St. Louis. The storm began in west-central Missouri and produced five tornadoes, damaging winds and then the hailstorm in St. Louis. Total insured losses alone were estimated to be $2.2 billion.
Two more of the costliest hailstorms on record were in Minneapolis, Minnesota, in May 1998 ($1.73 billion in insured losses) and the infamous Mayfest hailstorm in Fort Worth, Texas, in May 1995 ($2 billion in damage).
Bowen said the time of day is an important factor in hailstorm losses.
"If an event happens overnight, there is a possibility of reducing the cost due to vehicles being parked in garages. As compared to a late weekday afternoon when cars are parked in open lots or residents are driving home during rush hour," he said.
In other words, the combination of numerous damaged vehicles and homes usually adds up to the costliest hailstorms.
What a Hailstorm Can Do
Siding was damaged and windows were blown out in a hailstorm on July 10, 2016, in Killdeer, North Dakota. (Chris Sand/Instagram)
As a general rule of thumb, damage to roof shingles can occur with hail as small as quarter-size (1-inch diameter).
"When hail hits a roof, the entire roof is replaced even if there is partial damage," said Bryan Wood of Assurant, Inc.
That can cost about $5,000 to $10,000.
In rare cases of softball-size hail, typically found only in the Plains states a few times a year, hailstones can punch through the roof, leading to water damage in a home's interior.
(MORE: String of Damaging Spring 2016 Hailstorms)
Winds only worsen the damage potential.
Wood said that wind-driven hailstones can damage not only the roof, but also a home's siding, windows and doors.
"In these type of events, the damage (to a home) can exceed $30,000."
Patrick Clark inspects his damaged car after a strong spring storm moved through the metropolitan Denver area Monday afternoon, May 8, 2017.(AP Photo/P. Solomon Banda)
Typically, hail of golf-ball size– roughly 1.75 inches in diameter – begins to leave dents on vehicles.
Smashed windshields, not simply large cracks, typically result from hail of baseball-size or larger.
In some cases, the damage from hail can render a vehicle undriveable.
Roughly half the vehicles damaged in the May 2017 Denver hailstorm weren't drivable afterward, the Denver Post reported.
If you have time to do so safely, pull your vehicle into a garage, carport or parking garage when a severe thunderstorm warning for your area mentions large hail, no matter the size.
(MORE: Don't Ignore Severe Thunderstorm Warnings)
This may save you the hassle of repairing or replacing your vehicle and filing an insurance claim while hundreds, if not thousands of others are doing the same.
The Rocky Mountain Insurance Inormation Association has a list of steps to take if your home or vehicle is damaged by a hailstorm.
As destructive as hailstorms can be to your property, they can be devastating to crops.
Depending on the size of the field and the hail swath, damage can range from moderate to a total loss.
As with homes and vehicles, high winds only make the damage worse.
In hail-prone areas of the country, farmers typically carry insurance either specifically for hail damage, or a multiple-peril policy to insure against a number of threats such as high winds, fire, and hail.
The future looks no less costly from hailstorms.
"Since the 1970s, the average square footage of a home has increased from 1,500 to about 2,200 square feet," said Wood. "As homes get bigger, there is more surface area to be damaged."
Then there's suburban sprawl.
"With increasingly dense populations found in the most vulnerable convective storm belts of the country combining with increasingly intense hail events, that is a recipe for more costly events," said Bowen.
Essentially, Wood said there are increasingly more targets to be hit because of population growth.
(MORE: Fewer, But Bigger Hailstorms Ahead in a Warmer Climate)
Jonathan Erdman is a senior meteorologist at weather.com and has been an incurable weather geek since a tornado narrowly missed his childhood home in Wisconsin at age 7. Follow him on Facebook and Twitter.
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