Hail is a form of solid precipitation. It is distinct from ice pellets, though the two are often confused. It consists of balls or irregular lumps of ice, each of which is called a hailstone. Ice pellets generally fall in cold weather, while hail growth is greatly inhibited during low surface temperatures.
A thunderstorm, also known as an electrical storm or a lightning storm, is a storm characterized by the presence of lightning and its acoustic effect on the Earth's atmosphere, known as thunder. Relatively weak thunderstorms are sometimes called thundershowers. Thunderstorms occur in a type of cloud known as a cumulonimbus. They are usually accompanied by strong winds and often produce heavy rain and sometimes snow, sleet, or hail, but some thunderstorms produce little precipitation or no precipitation at all. Thunderstorms may line up in a series or become a rainband, known as a squall line. Strong or severe thunderstorms include some of the most dangerous weather phenomena, including large hail, strong winds, and tornadoes. Some of the most persistent severe thunderstorms, known as supercells, rotate as do cyclones. While most thunderstorms move with the mean wind flow through the layer of the troposphere that they occupy, vertical wind shear sometimes causes a deviation in their course at a right angle to the wind shear direction.
A supercell is a thunderstorm characterized by the presence of a mesocyclone; a deep, persistently rotating updraft. Due to this, these storms are sometimes referred to as rotating thunderstorms. Of the four classifications of thunderstorms, supercells are the overall least common and have the potential to be the most severe. Supercells are often isolated from other thunderstorms, and can dominate the local weather up to 32 kilometres (20 mi) away. They tend to last 2–4 hours.
Severe storms in Australia refers to the storms, including cyclones, which have caused severe damage in Australia. For comparison, a comprehensive list of all damaging storms can be found on the Australian Bureau of Meteorology website.
Severe weather is any dangerous meteorological phenomenon with the potential to cause damage, serious social disruption, or loss of human life. Types of severe weather phenomena vary, depending on the latitude, altitude, topography, and atmospheric conditions. High winds, hail, excessive precipitation, and wildfires are forms and effects of severe weather, as are thunderstorms, downbursts, tornadoes, waterspouts, tropical cyclones, and extratropical cyclones. Regional and seasonal severe weather phenomena include blizzards (snowstorms), ice storms, and duststorms.
The tornado outbreak of April 10–11, 2001, was a large tornado outbreak which affected the central Great Plains on April 10–11, 2001. During the two-day outbreak, it produced a total of 79 tornadoes across eight states including Kansas, Missouri, Oklahoma, Texas, Nebraska, Iowa, Illinois and Michigan. Four people were killed, 18 injured, and more than $23 million in damage was reported. The fatalities were reported in Oklahoma, Iowa and Missouri including two from a single tornado in Wapello County, Iowa.
The 1999 Sydney hailstorm was the costliest natural disaster in Australian insurance history, causing extensive damage along the east coast of New South Wales. The storm developed south of Sydney on the afternoon of Wednesday, 14 April 1999, and struck the city's eastern suburbs, including the central business district, later that evening.
A series of destructive severe thunderstorms struck southeastern Queensland, Australia, on 29 November 1992. The storms produced strong winds, flash flooding and large hailstones in the region, including the capital city of Brisbane. The storms also spawned two of the most powerful tornadoes recorded in Australia, including the only Australian tornado to be given an official 'F4' classification on the Fujita scale and the last violent tornado in Australia until 21 March 2013.
Extreme weather events in Melbourne, Australia have occurred on multiple occasions. The city has experienced a number of highly unusual weather events and extremes of weather. An increase in heat waves and record breaking temperatures in the 21st century has led to much discussion over the effects of climate change in the country.
The 1995 Mayfest storm was a damaging hailstorm that struck parts of the Dallas–Fort Worth metroplex on May 5, 1995. It was the first singular thunderstorm with a damage toll exceeding $1 billion and at the time the costliest nontornadic thunderstorm in U.S. history. Hail up to 4.5 in (11.5 cm) in diameter fell across Parker and Tarrant counties, producing hail drifts as deep as 3 ft (0.91 m) and damaging numerous buildings. The storm also struck the Fort Worth Mayfest – a local outdoor festival – pelting the roughly 10,000 people in attendance with softball-sized hail and resulting in over 60 hospitalizations. Though there were no hail-related fatalities, the combination of the slow-moving supercell that produced the hail and a larger complex of storms led to deadly flash flooding that killed 17 people in the Dallas area. Overall, 20 people were killed by the storms.
The 2010 Victorian storms were a series of storms that passed through much of the Australian state of Victoria on 6 and 7 March 2010. One of the most severe storms passed directly over Greater Melbourne, bringing lightning, flash flooding, very large hail and strong winds to the state's capital.
The 2010 Western Australian storms were a series of storms that travelled over southwestern Western Australia on 21 and 22 March 2010. One of the more intense storm cells passed directly over the capital city of Perth between 3:30pm and 5:00pm on Monday 22 March 2010. It is the costliest natural disaster in Western Australian history, with the damage bill estimated at $1.08 billion.
Severe Tropical Cyclone Yasi was a powerful and destructive tropical cyclone that made landfall in northern Queensland, Australia in early 2011, causing major damage to the affected areas. Originating as a tropical low near Fiji on 26 January, the system intensified to tropical cyclone status during the evening of 30 January. Yasi deepened rapidly over the next 24 hours, and was classified as a Category 3 cyclone at about 5 PM AEST on 31 January 2011. Late on 1 February, the cyclone strengthened to a Category 4 system; then, early on 2 February, the cyclone intensified into a Category 5 Severe Tropical Cyclone. The system had a well-defined eye and continued to track west-southwestward, maintaining a central pressure of 930 hPa and a Dvorak intensity of T6.5 into the evening.
On October 5–6, 2010, a destructive series of thunderstorms struck Arizona, resulting in the state's largest tornado outbreak and its costliest weather disaster on record. Spawned by a nearby cold-core low, successive hailstorms in Phoenix and surrounding locations on October 5 caused damage to thousands of homes, businesses, and vehicles. The following day, a record 12 tornadoes were recorded, multiple strong/EF2 or greater on the Enhanced Fujita scale and many in close proximity to one another; this included two tornadoes rated EF3. Thunderstorms on both days caused significant flash flooding which inundated businesses, stranded vehicles, and closed roadways. Damage throughout the state reached $4.9 billion, including $2.7 billion in insured loss from just hail damage, the costliest weather event on record in Arizona. Some impacts occurred in California, Nevada, and Utah as well as the cold-core remained stationary over several days.
The 2014 Brisbane hailstorm struck Brisbane, the capital city of Queensland, Australia on 27 November 2014. The storm caused severe damage to many buildings and cars in the city. Around 40 people were injured. Wind speeds of 141 km/h (88 mph) were recorded with multiple reports of hail in the city and surrounding areas.
Hailstorm Alley is a colloquial term referring to an area of south and central Alberta, Canada where hail storms are frequently produced. These storms frequently produce hail that is damaging to property. This area stretches from High River in southern Alberta, northward through Calgary, through Red Deer to Lacombe and then westward to Rocky Mountain House. It is known to be one of the worst areas in the world for damaging hail produced by thunderstorms. These are regarded as loose boundaries. While this area is common for damaging hailstorms, the reality is damaging hailstorms occur over much of central and southern Alberta every summer. The City of Calgary is regarded as the hailstorm capital of Canada.
Severe Tropical Cyclone Debbie in 2017 was the strongest tropical cyclone to strike Queensland since Marcia in 2015, and was the costliest tropical cyclone in Australia since Yasi in 2011. Forming as a tropical low on 23 March, the low gradually intensified into a named tropical cyclone on 25 March. After steadily strengthening offshore to a Category 4 system, Debbie eventually made landfall near Airlie Beach, at 12:40 AEST on 28 March. Afterwards, Debbie rapidly weakened into a tropical low by late 28 March, but continued to travel south, causing significant damage and flooding in the populous areas of South East Queensland and Northern Rivers. In total, the storm caused A$3.5 billion (US$2.67 billion) in damage and fourteen deaths across Australia, primarily as a result of extreme flooding. This makes Debbie the deadliest cyclone to hit Australia since Fifi in 1991.
The July 1968 United Kingdom thunderstorms were the most severe dust fall thunderstorms in the British Isles for over 200 years. A layer of mineral dust blowing north from the Sahara met cold, wet air over the British Isles, resulting in thick, dense clouds and severe thunderstorms across most of England and Wales. These clouds completely blotted out the light in some areas and the rain and hail resulted in property damage and flooding, and at least four people were killed. During the storm, Leeming Bar in North Yorkshire saw 35.7 millimetres (1.41 in) of rain in under 10 minutes – a UK record until 2003.
Severe weather events or extreme weather events in Sydney, Australia, include hailstorms, thunderstorms, gale, bushfires, heatwaves, drought, and flash flooding from heavy rain. Sydney is rarely affected by cyclones, although remnants of cyclones do affect the city.
