Bob Dylan wasn’t referencing hail when he wrote “A Hard Rain’s A-Gonna Fall” back in ’62 but as innumerable dimpled cars, flattened fields and fractured skulls can attest, hail is as hard as rain can get.
When the New York City General Post Office was being designed back in the 1890s, someone at the architectural firm McKim, Mead and White thought that the motto “Neither snow nor rain nor heat nor gloom of night stays these couriers from the swift completion of their appointed rounds” would make a great motto for the building’s exterior facade.
(image via: Arty Smokes)
Originally attributed to the ancient Greek historian Herodotus, the motto does NOT mention one of the most frightening and dangerous weather conditions postmen – or anyone else required to perform their duties outdoors – must deal with: hail.
Hail, in its mildest form, superficially resembles sleet (a mix of snow and rain) but both the conception and the consequences of the former can be much more severe. That’s because hail is associated with thunderstorms and their massive, spectacularly high anvil-shaped clouds. Inside these supercells, updrafts roaring at up to 110 miles per hour (180 km/h) take water droplets and ice crystals on a rollercoaster ride spanning tens of thousands of feet.
During the course of repeated trips up and down through these ominous cumulonimbus clouds, a barely visible ice crystal can grow to astonishing sizes and often strange shapes. The process can be compared to the making of homemade candles: with each dip in hot wax, the candle adds another layer. Hailstones continue to grow until their sheer weight overcomes the strength of the storm’s updrafts.
Hail can fall with little warning, especially when storm clouds are close and rain is already falling heavily. When visibility permits, however, it’s possible to discern certain features that are distinct to hailstorms. One of these is the so-called “hail shaft”, which indicates hail falling at a distance in a sharply defined swath. Another is more curious: hail clouds sometimes take on an odd, greenish shade.
A wide variety of terms are used to describe the size of hailstones, including pea-sized, dime-sized, golfball-sized and baseball-sized. While the size of hailstones is one factor in estimating the damage they may cause to objects on the ground, another is their speed, or terminal velocity. In general, as hailstones get bigger their speed increases – to over 100 miles per hour (160 k/ph) in some cases.
How big can a hailstone get? The current champion hailed from (actually, on) Aurora, Nebraska, USA. This monster, which fell during a storm in 2003, was measured at 7 inches (17.78 cm) in diameter. “I looked outside, and it was raining volleyballs,” said Dale Obermeier, an Aurora farmer and National Weather Service spotter. Imagine what that bad boy and its brothers could do to your cornfield, not to mention your cabeza. Just below the Aurora hailstone is a cross-section of the previous record-holder, a 1.67 pound (0.75 kg) and 5.5 inch (13.75 cm) wide monster that fell (very loudly, most likely) near Coffeyville, Kansas, in 1970.
Thunderstorms, even those accompanied by huge supercells that unleash blistering downpours and swarms of tornadoes, don’t always include hail in their arsenal. Some regions of the world appear to be more prone to hail and hailstorms, with common contributing factors being nearby mountain ranges that can accentuate updrafts. In the United States, the area where the states of Colorado, Nebraska, and Wyoming meet is known colloquially as “Hail Alley.” Residents in this area may expect hail to fall 7 to 9 days each year.
Hail has always been the bane of farmers, whose crops can be severely damaged by hail of even a modest size. Hundreds of millions of dollars are spent annually by American farmers on hail insurance – it may be said that hailstones are the locusts of the modern age.
Property damage caused by hail is not a new issue but one growing in importance as cities and their infrastructure continue to expand. Hail is problematic for homeowners, corporations and governmental authorities because although damaging hailstorms are rather rare, when they do strike the effects can be severe. The above images show hail damage on different types of roofing materials. Even slate roofs can suffer a shocking amount of damage after being bombarded by large hailstones traveling at speed. Greenhouses have no chance at all.
Automobiles and aircraft are also extremely susceptible to hail damage, manifested in two main ways: dimpling of sheet metal and, in the case of larger hailstones, cracked or shattered windshields and sunroofs.
The devastation above occurred in Sydney, Australia, during the course of an exceptionally vicious hailstorm that left cars, roofs, even patio furniture in tatters. The April 14th, 1999 hailstorm dropped approximately half a million tons of hail and was Australia’s most costly natural disaster.
The blue covers on the roofs above indicate were significant damage from hailstones occurred during the 1999 Sydney hailstorm. Considering the scope and cost of the damage it’s a wonder only a single person lost their life: a man who was struck by lightning while in his boat.
(image via: Wikimedia)
Sydney has seen severe hailstorms before – the above image was taken during a storm that struck the city and its environs in 1947. The image may remind some of a recent very popular (nearly 4 million views) YouTube video that recorded hundreds of large hailstones slamming into a swimming pool… here it is, if you haven’t seen it yet:
(images via: More Cool Pictures)
Damage to property is one thing, injuries to people, pets and livestock caught outdoors during a hailstorm can be horrific. Often no shelter is available when hailstones suddenly begin to fall: sheep or cattle grazing in meadows and joggers on open trails are prime examples – and easy targets.
The unfortunate person above was one of a group of 4 college students jogging in Grinnell (near Des Moines), Iowa. Golfball-sized hail driven by winds of up to 75 miles per hour (120 kp/h) left the boys with dozens of painful raised welts, suspected broken ribs and a quick trip to the hospital. In July of 1990, 47 people in Denver, Colorado suffered a variety of serious injuries when a power outage trapped them on an amusement park Ferris wheel, where they were bombarded by hailstones the size of softballs!
Hail can indeed be deadly – although records in the United States list only 5 fatalities (the most recent in the year 2000) that can be definitely ascribed to hail, other nations have been much more seriously affected. India, in particular, has a long history of deadly hailstorms with the most notable occurring in 1888 when 246 people lost their lives. It has recently been determined, however, that an even greater hail-caused tragedy occurred centuries earlier at Skeleton Lake in Roopkund, India.
Roopkund is located 16,499 feet (5,029 meters) above sea level in northern India’s Uttarakhand state. The area is exceedingly barren and completely treeless. Sometime in the 9th century, a large religious procession was traversing the area when it was overtaken by a sudden, severe hailstorm.
It’s not known how many of the pilgrims survived the terrifying icy onslaught but today the remains of as many as 600 people can be found scattered in and around Skeleton Lake – a glacial lake so named after park rangers stumbled upon the macabre scene while on patrol in 1942.
(image via: Passing Parade)
Judging by the injuries seen on human skulls found at Skeleton Lake, scientists determined that the deaths of the pilgrims could only have been caused by the deadly impact of large hailstones the size of cricket balls.
(image via: More Cool Pictures)
Hail’s effect on human history, society and culture is incalculable. Imagine being a Neanderthal swept up in a hailstorm while hunting mammoths, one of the poor pilgrims at Roopkund who trusted in the mercy of a capricious God, or a 21st century college kid out for a carefree weekend jog… look up and look out, ’cause you never know when The Iceman Cometh.