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Hail is a form of precipitation which consists of balls or irregular lumps of ice (hailstones). Hailstones on Earth usually consist mostly of water ice and measure between 5 and 50 millimeters in diameter, with the larger stones coming from severe thunderstorms.^[1] Hail is only produced by cumulonimbi (thunderclouds), usually at the front of the storm system, and is composed of transparent ice or alternating layers of transparent and translucent ice at least 1 mm thick. The METAR code for hail 5 mm or greater in diameter is GR, while smaller hailstones and graupel are coded GS. Unlike ice pellets, they are layered and can be irregular and clumped together. This article is about Earth as a planet. ... This article is about water ice. ... A shelf cloud associated with a heavy or severe thunderstorm over Enschede, The Netherlands. ... Cumulonimbus cloud in central Oklahoma. ... METAR (for METeorological Aerodrome Report) is a format for reporting weather information. ... Graupel can be any of the following types of solid-ice precipitation: hail - large chunks of ice such as from a strong or severe thunderstorm sleet - small pellets of raindrops that have frozen in mid-air, in winter or a thunderstorm snow pellets - when freezing fog forms 2-5mm balls... Sleet can refer to at least two different forms of precipitation. ...

Hail formation

A large hailstone, about 6 cm (2.36 in) in diameter

Hail forms in storm clouds when supercooled water droplets freeze on contact with condensation nuclei, such as dust. The storm's updraft blows the hailstones to the upper part of the cloud. The updraft dissipates and the hailstones fall down, back into the updraft, and are lifted up again. The hailstone gains an ice layer and grows increasingly larger with each ascent. Once a hailstone becomes too heavy to be supported by the storm's updraft, it falls out of the cloud. Image File history File links Download high resolution version (1840x1192, 923 KB) Description: Aggregate hailstone. ... Image File history File links Download high resolution version (1840x1192, 923 KB) Description: Aggregate hailstone. ... For other uses, see Cloud (disambiguation). ... Supercooling is the process of chilling a liquid below its freezing point, without its becoming solid. ... Impact from a water drop causes an upward rebound jet surrounded by circular capillary waves. ... Aerosol pollution over Northern India and Bangladesh - NASA Cloud condensation nuclei or CCNs (also known as cloud seeds) are small particles (typically 0. ... Look up dust in Wiktionary, the free dictionary. ... An Updraft or Downdraft is refers to the vertical movement of air as a weather related phenomenom. ...

In large hailstones, latent heat released by further freezing may melt the outer shell of the hailstone. The hailstone then may undergo 'wet growth', where the liquid outer shell accretes other smaller hailstones. In thermochemistry, latent heat is the amount of energy in the form of heat released or absorbed by a substance during a change of phase (i. ...

Ideal conditions for hail formation

The largest hailstone ever measured, 17.8 centimetres (7.0 in) in diameter with a 47.6 centimetres (19 in) circumference.

Hail forms in strong thunderstorm clouds, particularly those with intense updrafts, high liquid water content, great vertical extent, large water droplets, and where a good portion of the cloud layer is below freezing 0 °C (32 °F). The growth rate is maximized at about −13 °C (9 °F), and becomes vanishingly small much below −30 °C (−22 °F) as supercooled water droplets become rare. For this reason, hail is most common in mid-latitudes during early summer where surface temperatures are warm enough to promote the instability associated with strong thunderstorms, but the upper atmosphere is still cool enough to support ice. Accordingly, hail is actually less common in the tropics despite a much higher frequency of thunderstorms than in the mid-latitudes because the atmosphere over the tropics tends to be warmer over a much greater depth.^{[citation needed]} Also, entrainment of dry air into strong thunderstorms over continents can increase the frequency of hail by promoting evaporational cooling which lowers the freezing level of thunderstorm clouds giving hail a larger volume to grow in. Image File history File links Hailstone. ... Image File history File links Hailstone. ... Weather is a term that encompasses phenomena in the atmosphere of a planet. ... DIAMETER is a computer networking protocol for AAA (Authentication, Authorization and Accounting). ... The circumference is the distance around a closed curve. ... A shelf cloud associated with a heavy or severe thunderstorm over Enschede, The Netherlands. ... An Updraft or Downdraft is refers to the vertical movement of air as a weather related phenomenom. ... See entrainment for other types. ...

Hail is also much more common along mountain ranges because mountains force horizontal winds upwards (known as orographic lifting), thereby intensifying the updrafts within thunderstorms and making hail more likely. One of the most notorious regions for large hail is the mountainous northern India and Bangladesh, which have reported more hail-related deaths than anywhere else in the world and also some of the largest hailstones ever measured. Mainland China is also notorious for killer hailstorms. Certain locations in North America (such as the area around Calgary, Alberta, Houston, Texas, and St. Louis, Missouri) have gained the nickname "Hailstorm Alley" among meteorologists for the frequency of hailstorms and their severity.^[2] This wave cloud pattern formed off of the ÃŽle Amsterdam in the far southern Indian Ocean, due to orographic lift of an airmass by the island, producing alternating bands of condensed and invisible humidity downwind of the island as the moist air moves in vertical waves and the moisture successively... ... This article is about the Canadian city. ... For other uses, see Alberta (disambiguation). ... Houston redirects here. ... St. ...

Hailstones, while most commonly only a few millimetres in diameter, can sometimes grow to 15 centimetres (6 in) and weigh more than .5 kilograms (1.1 lb)^[3]. Pea or golf ball-sized hailstones are not uncommon in severe storms. Hail can do serious damage, notably to automobiles, skylights, glass-roofed structures, and most commonly, farmers' crops. Rarely, massive hailstones have been known to cause concussions or fatal head trauma. Sometimes, hail-producing clouds are identifiable by their green colouration.^[4][5] DIAMETER is a computer networking protocol for AAA (Authentication, Authorization and Accounting). ... Binomial name L. Percentages are relative to US recommendations for adults. ... This article is about the game. ... Cerebral Concussion redirects here. ... In medicine, a trauma patient has suffered serious and life-threatening physical injury resulting in secondary complications such as shock, respiratory failure and death. ...

Short term detection

In the United States, to issue proper warnings and forecasts, National Weather Service uses a network of NEXRAD doppler radars to detect hail. Hail size and probability can be determined from radar data by a computer by different algorithms. This, in combination with an analysis of the radar display is an accurate way of detecting hail. An analysis of the radar data would include viewing reflectivity data at multiple angles above ground level to check for hail development in the upper levels of the storm, and checking the Vertically Integrated Liquid (VIL). VIL and hail do have a relationship, although it varies with atmospheric conditions and therefore is not highly accurate. Radar data can also be complimented by a knowledge of current atmospheric conditions which can allow one to determine if the current atmosphere is conducive to hail development. NEXRAD Radar at NSSL NEXRAD or Nexrad (Next-Generation Radar) is a network of 158 high-resolution Doppler radars operated by the National Weather Service, an agency of the National Oceanic and Atmospheric Administration (NOAA), in the United States. ...

Size scale

The examples and perspective in this section may not represent a worldwide view of the subject. Please improve this article or discuss the issue on the talk page.

Hailstone size is often reported as compared to known objects rather than by reporting the actual diameter. Below is a table of commonly used objects for this purpose.^[6] The UK organisation, TORRO, also scales for both hailstones and hailstorms.^[7] Percussion for Orange Pecco and Olla Vogola Barkeeper at Kinky Star ...

Binomial name L. Percentages are relative to US recommendations for adults. ... For other uses, see Dime. ... The United States one-cent coin is a unit of currency equaling one-hundredth of a United States dollar. ... The United States five-cent coin, commonly called a nickel, is a unit of currency equaling one-twentieth, or five hundredths, of a United States dollar. ... A quarter is a coin worth one-quarter of a United States dollar, or 25 cents. ... The Half Dollar of the United States has been produced nearly every year since the inception of the United States Mint in 1794. ... For other uses, see Walnut (disambiguation). ... A golf ball next to a hole A golf ball is a ball designed for use in the game of golf. ... A green Penn tennis ball. ... A baseball A baseball, is a ball used primarily in the sport of the same name, baseball. ... Binomial name Macfad. ... Softball is a team sport popular especially in the United States. ...

Costly or deadly hailstorms

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Hail clouds often exhibit a characteristic green coloration.

• Around the 9th century, several hundred pilgrims were killed by a massive hailstorm in Roopkund, Uttarakhand, India.^[8]
• December 1967, A hailstorm hit Los Angeles County, blanketing the region much like a snowstorm. The storm also produced lightning, and one bolt struck an oil tank in Manhattan Beach, causing an explosion that covered much of the South Bay with the oil. The next hailstorm to hit the area was in 1979.^{[citation needed]}
• July 11, 1990, Denver, Colorado, USA, Softball-sized hail destroyed roofs and cars, causing $625 million in total damage.
• September 7, 1991: a Labour Day thunderstorm caused $400 million worth of insurable damage in Calgary, Alberta, Canada. Thirteen additional hailstorms between 1981 and 1998 caused an estimated $600 million in damage in the Calgary area alone.^[9][10]
• May 5, 1995, Dallas and Fort Worth, Texas, USA, $1.1 billion insured losses, total storm damage reported at around $2 billion. The storms produced hail about the size of softballs.^[11][12][13]
• April 14, 1999, Sydney, New South Wales, Australia, $1.5 billion. 20,000 properties and 40,000 vehicles were damaged during the storm with more than 25 aircraft damaged at Sydney Airport, one person was killed while fishing after getting struck by lightning and several other people were injured. It was the costliest hailstorm to hit an Australian populated city.^[14] Largest stone measured was 9.5 cm.^[15]
• March 29, 2000, The last known hail fatality in the United States occurs. The victim was Juan Oseguera, a nineteen-year-old man who died from head injuries after being hit by a softball sized hailstone in Lake Worth, Texas. ^[16]
• May 18, 2000, McHenry, Lake, northern Kane, and northern Cook County, Illinois, USA, $572 million ^[17]. Golfball-, baseball-, and softball-sized hail damaged roofs, cars, patio furniture, skylights, and windows in the area's worst and most widespread hailstorm in 30 years. Around 100,000 homes lost power. Hail was 3 inches (76 mm) deep in many areas. There were 100 canceled flights, and train service was disrupted. ^[18][19]
• April 10, 2001, St. Louis, Missouri, USA, $2.0 billion+. The costliest hailstorm in US history struck the I-70 corridor of eastern Kansas, across Missouri, into southwestern Illinois.^[20]
• July 19, 2002, Henan Province, the People's Republic of China, 25 dead and hundreds injured.
• The largest hailstone on record fell on June 22, 2003 in Aurora, Nebraska, USA. It has a 7-inch (180 mm) diameter and a circumference of 18.75 inches (476 mm).
• April 20 – April 21, 2006, San Marcos, Texas, USA, hail of sizes up to 10 cm^[21][22] results in 10,000 auto claims, 7,000 homeowner and commercial property claims ranging between $100-160 million insured losses.^[23][24] One woman was hospitalized.^[25] The storm was especially costly at the San Marcos Outlet Malls and a nearby Toyota dealership.^[26][27]
• June 28 – June 29, 2006, Villingen-Schwenningen and suburbs, Baden-Württemberg, Germany, supercell thunderstorms, severe damage by very large hailstones (softball-size), causing € 150 million damage, more than 100 fatalities.
• December 9, 2007, Sydney, New South Wales, Australia, Severe thunderstorms caused immense damage in the North and Western Suburbs of Sydney. Worst hit were the suburbs of Blacktown, Castle Hill and neighbouring Baulkham Hills. Hail stones the size of golf balls damaged cars, windows and homes. Largest hail stones reached almost 10 cm in diameter in Kings Langley.^[28]

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Roopkund is a place in Uttaranchal India, the location of about three to six hundred skeletons at the edge of a lake—Skeleton Lake in the Himalayas. ... , Uttarakhand (Hindi: उत्तराखण्ड or उत्तराखंड), is a state located in the northern part of India. ... Map of California showing Los Angeles County. ... Not to be confused with lighting. ... Location of Manhattan Beach in Los Angeles County, California Coordinates: , Country State County Los Angeles Incorporated (city) 1912-12-12 [2] Government  - Mayor Jim Aldinger [1] Area  - Total 10. ... is the 192nd day of the year (193rd in leap years) in the Gregorian calendar. ... This article is about the year. ... Nickname: Location of Denver in the State of Colorado Location of Colorado in the United States Coordinates: , Country United States State State of Colorado City and County Denver[1] Founded 1858-11-22, as Denver City, K.T.[2] Incorporated 1861-11-07, as Denver City, C.T.[3] Consolidated... 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Nickname: Motto: Where the West Begins Location of Fort Worth in Tarrant County, Texas Coordinates: , Country State Counties Tarrant, Denton Government  - Mayor Michael J. Moncrief Area  - City 298. ... Motto: (traditional) In God We Trust (official, 1956–present) Anthem: The Star-Spangled Banner Capital Washington, D.C. Largest city New York City Official language(s) None at the federal level; English de facto Government Federal Republic  - President George W. Bush (R)  - Vice President Dick Cheney (R) Independence - Declared - Recognized... is the 104th day of the year (105th in leap years) in the Gregorian calendar. ... Events of 2008: (EMILY) Me Lesley and MIley are going to China! This article is about the year. ... This article is about the metropolitan area in Australia. ... NSW redirects here. ... The 1999 Sydney hailstorm caused more property damage than any other natural disaster in Australian history, causing extensive damage along the east coast of New South Wales. ... is the 88th day of the year (89th in leap years) in the Gregorian calendar. ... Year 2000 (MM) was a leap year starting on Saturday. ... Lake Worth is a city in Tarrant County, Texas, United States. ... is the 138th day of the year (139th in leap years) in the Gregorian calendar. ... Year 2000 (MM) was a leap year starting on Saturday. ... McHenry County is located in the U.S. state of Illinois. ... Lake County is a county located in the U.S. state of Illinois. ... Location in the state of Illinois Formed January 16, 1836 Seat Geneva Area  - Total  - Water 1,357 km² (524 mi²) 9 km² (4 mi²) 0. ... Cook County is a county located in the U.S. state of Illinois. ... This article is about the U.S. State. ... Motto: (traditional) In God We Trust (official, 1956–present) Anthem: The Star-Spangled Banner Capital Washington, D.C. Largest city New York City Official language(s) None at the federal level; English de facto Government Federal Republic  - President George W. Bush (R)  - Vice President Dick Cheney (R) Independence - Declared - Recognized... is the 100th day of the year (101st in leap years) in the Gregorian calendar. ... This article is about the year. ... St. ... This article is about the U.S. state. ... Motto: (traditional) In God We Trust (official, 1956–present) Anthem: The Star-Spangled Banner Capital Washington, D.C. Largest city New York City Official language(s) None at the federal level; English de facto Government Federal Republic  - President George W. Bush (R)  - Vice President Dick Cheney (R) Independence - Declared - Recognized... 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Year 2003 (MMIII) was a common year starting on Wednesday of the Gregorian calendar. ... Hamilton County courthouse Aurora is a city located in Hamilton County, Nebraska in the United States of America. ... Motto: (traditional) In God We Trust (official, 1956–present) Anthem: The Star-Spangled Banner Capital Washington, D.C. Largest city New York City Official language(s) None at the federal level; English de facto Government Federal Republic  - President George W. Bush (R)  - Vice President Dick Cheney (R) Independence - Declared - Recognized... is the 110th day of the year (111th in leap years) in the Gregorian calendar. ... is the 111th day of the year (112th in leap years) in the Gregorian calendar. ... Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ... Image:Marcos. ... Motto: (traditional) In God We Trust (official, 1956–present) Anthem: The Star-Spangled Banner Capital Washington, D.C. Largest city New York City Official language(s) None at the federal level; English de facto Government Federal Republic  - President George W. Bush (R)  - Vice President Dick Cheney (R) Independence - Declared - Recognized... Toyota Motor Corporation ) is a multinational corporation headquartered in Japan, and currently is the worlds largest automaker. ... is the 179th day of the year (180th in leap years) in the Gregorian calendar. ... is the 180th day of the year (181st in leap years) in the Gregorian calendar. ... Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ... Villingen-Schwenningen is the largest city of the Schwarzwald-Baar district located in the south of Baden-Württemberg, Germany. ... Location Coordinates , , Time zone CET/CEST (UTC+1/+2) Administration Country NUTS Region DE1 Capital Stuttgart Minister-President Günther Oettinger (CDU) Governing parties CDU / FDP Votes in Bundesrat 6 (of 69) Basic statistics Area  35,752 km² (13,804 sq mi) Population 10,741,000 (11/2006)[1]  - Density... Satellite view of a supercell A supercell is a severe thunderstorm with a deep rotating updraft (a mesocyclone) [1]. Supercell thunderstorms are the largest, most severe class of single-cell thunderstorms. ... is the 343rd day of the year (344th in leap years) in the Gregorian calendar. ... Year 2007 (MMVII) was a common year starting on Monday of the Gregorian calendar in the 21st century. ... This is about the city of Sydney in Australia. ... Blacktown is a suburb in the City of Blacktown, in Western Sydney, in the state of New South Wales, Australia. ... This article does not cite any references or sources. ... Baulkham Hills is a suburb in the north-west of Sydney, in the state of New South Wales, Australia. ...

Gallery

This section may require cleanup to meet Wikipedia's quality standards. Please improve this article if you can (April 2008).

Hail Shaft Image File history File linksMetadata Hailshaft. ...	Small hail that has been fractured to show internal structure; 246x magnification. The inset shows the original hail. Image File history File linksMetadata Download high resolution version (1400x1562, 380 KB) Small hail that has been fractured to show internal structure. ...	Hailstorm in Bogotá, Colombia. Image File history File linksMetadata Bogota_hailstorm. ... Bogota redirects here. ...	A field littered with large hailstones right after a summer hailstorm. Image File history File linksMetadata Download high resolution version (1920x2560, 1312 KB) Summary Photographer: Soon Chun Siong Licensing I, the creator of this work, hereby release it into the public domain. ...
Hailstorm in Bogotá. Image File history File links No higher resolution available. ... Bogota redirects here. ...	Large hailstones up to 5 centimetres (2 in) in diameter with concentric rings. The coin diameter is 21 millimetres (0.8 in). Image File history File linksMetadata Download high resolution version (2560x1920, 966 KB) Summary Author: Soon Chun Siong Licensing I, the creator of this work, hereby release it into the public domain. ... 5 cent euro coins are made of a steel core plated with copper. ...	April 20, 2006 hailstorm on San Marcos, Texas Image File history File links Metadata Size of this preview: 449 × 600 pixelsFull resolution (1932 × 2580 pixel, file size: 1,017 KB, MIME type: image/jpeg) File historyClick on a date/time to view the file as it appeared at that time. ... is the 110th day of the year (111th in leap years) in the Gregorian calendar. ... Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ... Image:Marcos. ... For other uses, see Texas (disambiguation). ...	Flood caused by the November 4, 2007 Hailstorm in Bogotá, Colombia. Image File history File links No higher resolution available. ... is the 308th day of the year (309th in leap years) in the Gregorian calendar. ... Year 2007 (MMVII) was a common year starting on Monday of the Gregorian calendar in the 21st century. ... Bogota redirects here. ...
Hailstorm Wikipedia does not have an article with this exact name. ...

See also

• Sleet
• Graupel
• Snow grains
• Hail cannon

Sleet is a term used in a variety of ways to describe precipitation intermediate between rain and snow but distinct from hail. ... Graupel can be any of the following types of solid-ice precipitation: hail - large chunks of ice such as from a strong or severe thunderstorm sleet - small pellets of raindrops that have frozen in mid-air, in winter or a thunderstorm snow pellets - when freezing fog forms 2-5mm balls... Snow grains are a form of precipitation characterized as: white, opaque grains of ice very small <1 mm, fairly flat or enlongated, unlike Snow pellets they dont bounce or breakup on impact, very small amounts fall, mostly from Stratus or Fog, Never in the form of a shower. ... There are very few or no other articles that link to this one. ...

References

The National Oceanic and Atmospheric Administration (NOAA) is a scientific agency of the United States Department of Commerce focused on the conditions of the oceans and the atmosphere. ...

Further reading

• Rogers and Yau (1989). A Short Course in CLOUD PHYSICS. Massachusetts: Butterworth-Heinemann. ISBN 0-7506-3215-1. 
• Jim Mezzanotte (2007). Hailstorms. Gareth Stevens Publishing. ISBN 978-0836879124. 
• Snowden Dwight Flora (2003). Hailstorms of the United States. Textbook Publishers. ISBN 978-0758116987. 
• Narayan R. Gokhale (1974). Hailstorms and Hailstone Growth. State University of New York Press. ISBN 978-0873953139. 
• Duncan Scheff (2001). Ice and Hailstorms. Raintree Publishers. ISBN 978-0739847039. 

External links

• Hail Research Information Center
• Images of hail and hailstorms
• Images of a major giant hail event in Brazil
• Hail factsheet
• Using sound to break up hail
• Youtube Video of large hailstorm in progress
• Social & Economic Costs of Hail from "NOAA Socioeconomics" website initiative

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Hail

Look up Hail, hail in Wiktionary, the free dictionary.