Portal:Weather

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Weather refers to the state of the Earth's atmosphere at a specific place and time, typically described in terms of temperature, humidity, cloud cover, and stability. On Earth, most weather phenomena occur in the lowest layer of the planet's atmosphere, the troposphere, just below the stratosphere. Weather refers to day-to-day temperature, precipitation, and other atmospheric conditions, whereas climate is the term for the averaging of atmospheric conditions over longer periods of time. When used without qualification, "weather" is generally understood to mean the weather of Earth.

Weather is driven by air pressure, temperature, and moisture differences between one place and another. These differences can occur due to the Sun's angle at any particular spot, which varies with latitude. The strong temperature contrast between polar and tropical air gives rise to the largest scale atmospheric circulations: the Hadley cell, the Ferrel cell, the polar cell, and the jet stream. Weather systems in the middle latitudes, such as extratropical cyclones, are caused by instabilities of the jet streamflow. Because Earth's axis is tilted relative to its orbital plane (called the ecliptic), sunlight is incident at different angles at different times of the year. On Earth's surface, temperatures usually range ±40 °C (−40 °F to 104 °F) annually. Over thousands of years, changes in Earth's orbit can affect the amount and distribution of solar energy received by Earth, thus influencing long-term climate and global climate change.

Surface temperature differences in turn cause pressure differences. Higher altitudes are cooler than lower altitudes, as most atmospheric heating is due to contact with the Earth's surface while radiative losses to space are mostly constant. Weather forecasting is the application of science and technology to predict the state of the atmosphere for a future time and a given location. Earth's weather system is a chaotic system; as a result, small changes to one part of the system can grow to have large effects on the system as a whole. Human attempts to control the weather have occurred throughout history, and there is evidence that human activities such as agriculture and industry have modified weather patterns.

Studying how the weather works on other planets has been helpful in understanding how weather works on Earth. A famous landmark in the Solar System, Jupiter's Great Red Spot, is an anticyclonic storm known to have existed for at least 300 years. However, the weather is not limited to planetary bodies. A star's corona is constantly being lost to space, creating what is essentially a very thin atmosphere throughout the Solar System. The movement of mass ejected from the Sun is known as the solar wind. (Full article...)

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Hurricane Floyd was the sixth named storm, fourth hurricane, and third major hurricane in the 1999 Atlantic hurricane season. Floyd triggered the third largest evacuation in US history (behind Hurricane Gustav and Hurricane Rita, respectively) when 2.6 million coastal residents of five states including Florida were ordered from their homes as Hurricane Floyd approached. The Cape Verde-type hurricane formed off the coast of Africa and lasted from September 7 to September 19, peaking in strength as a very strong Category 4 hurricane—just short of the highest possible rating—on the Saffir-Simpson Hurricane Scale. It was among the largest Atlantic hurricanes of its strength ever recorded.

Floyd struck The Bahamas at peak strength, causing heavy damage. It then paralleled the East Coast of the United States, causing massive evacuations and costly preparations. The storm weakened significantly, however, before making landfall in North Carolina as a Category 2 hurricane, and caused further damage as it traveled up the Mid-Atlantic region and into New England.

The hurricane produced torrential rainfall in eastern North Carolina, adding more rain to an area hit by Hurricane Dennis just weeks earlier. The rains caused widespread flooding over a period of several weeks; nearly every river basin in the eastern part of the state exceeded 500-year flood levels. In total, Floyd was responsible for 57 fatalities and $4.5 billion ($6.0 billion in 2008 U.S. dollars) in damage, mostly in North Carolina.

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Did you know (auto-generated) - show different entries

... that an attempted British-Norwegian attack on the German battleship Tirpitz was abandoned after two Chariot manned torpedoes were lost due to bad weather?
... that the apricot dress of Jacqueline Kennedy kept its shape in India's hot weather?
... that Come In was recorded on a hands-free microphone attached to a pair of headphones?
... that actress Jennifer Brooke and her colleagues faced severe weather from Storm Imogen while filming her death scene for Hollyoaks?
... that the Quad Cities forecast office of the National Weather Service has been directly struck by both an F1 tornado and a historic derecho?
... that environment minister Peng Chi-ming drafted Taiwan's first weather insurance policy?

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Mammatus (also known as mamma or mammatocumulus, meaning "breast-cloud") is a meteorological term applied to a cellular pattern of pouches hanging underneath the base of a cloud. The name "mammatus" is derived from the Latin mamma (breast), due to the resemblance between the shape of these clouds and human female breasts. Mammatus are most often found on the anvil cloud that extends from a cumulonimbus, and therefore are commonly associated with severe weather.

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...that the Flying river is the name given to the transport of water vapor from the Amazon rainforest to southern Brazil?

...that hurricane shutters are required for all homes in Florida unless impact-resistant glass is used?

...that the Joint Institute for Marine and Atmospheric Research is a combined weather and ocean research institute with the cooperation of the Office of Oceanic and Atmospheric Research and the University of Hawaiʻi?

...that the SS Central America was sunk by a hurricane while carrying more than 30,000 pounds (13,600 kg) of gold, contributing to the Panic of 1857?

...that a hurricane force wind warning is issued by the United States National Weather Service for storms that are not tropical cyclones but are expected to produce hurricane-force winds (65 knots (75 mph; 120 km/h) or higher)?

...that the Automated Tropical Cyclone Forecasting System is a software package for tropical cyclone forecasting developed in 1988 that is still used today by meteorologists in various branches of the US Government?

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January 6

1996: The Blizzard of '96 began pounding the Eastern United States, and would eventually dump 2–4 feet (0.61–1.2 m) of snow on an area from Tennessee to Massachusetts.

January 7

1987: A major cold snap began in the United Kingdom and Ireland, bringing temperatures as low as −23.3 °C (−9.9 °F) and up to 75 centimetres (30 in) of snow.

January 8

1988: Typhoon Roy passed near Majuro atoll, Marshall Islands, causing moderate damage across the island chain and killing one person.

January 9

1998: Cyclone Katrina, a long-lived South Pacific tropical cyclone that meandered east of Australia for more than three weeks, reached peak intensity northwest of Vanuatu, with 1-minute maximum sustained winds of 165 km/h (105 mph).

January 10

1973: A devastating tornado, the deadliest in South American history, killed 54 people in San Justo, Santa Fe, Argentina.

January 11

1898: A tornado killed 55 people in Fort Smith, Arkansas overnight. This is tied for the deadliest tornado in Arkansas state history.

January 12

2006: Cyclone Tam passed near Niuafoʻou, Tonga, but little damage was reported. The previous day, the storm dumped 293.2 millimetres (11.54 in) of rain on Rotuma, Fiji in just 24 hours, a record for the island.

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John Dalton FRS (/ˈdɔːltən/; 5 or 6 September 1766 – 27 July 1844) was an English chemist, physicist, and meteorologist whose work laid the foundations of modern atomic theory and stoichiometric chemistry. Building on earlier ideas about the indivisibility of matter and his own precise measurements of combining ratios, Dalton proposed that each chemical element consists of identical atoms of characteristic weight, and that compounds are formed when atoms of different elements combine in fixed whole-number proportions. His A New System of Chemical Philosophy (1808) presented a coherent atomic model, supplied relative atomic weights and symbolic notation, and established the quantitative framework that shaped nineteenth-century chemistry and remains the basis of modern chemical thought.

Dalton was also a pioneering meteorologist and physicist, keeping daily weather observations for over fifty years, formulating the first empirical law of partial pressures (later known as Dalton’s Law), and studying the behavior of gases through his work on vapor pressure and gas solubility. His investigations into his own color blindness led to the first scientific description of the condition—still called Daltonism in several languages—and helped establish experimental methods for linking perception with physiology. Elected a Fellow of the Royal Society in 1822 and awarded its Royal Medal in 1826, Dalton became the first British scientist to develop a quantitative atomic theory and one of the key figures in the transition of chemistry from a qualitative to a mathematical science.

In honour of Dalton's work, a unit of atomic mass, the dalton, symbol Da, is officially accepted for use with the SI. (Full article...)

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WikiProjects

The scope of WikiProject Weather is to have a single location for all weather-related articles on Wikipedia.

WikiProject Meteorology is a collaborative effort by dozens of Wikipedians to improve the quality of meteorology- and weather-related articles. If you would like to help, visit the project talk page, and see what needs doing.

WikiProject Severe weather is a similar project specific to articles about severe weather. Their talk page is located here.

WikiProject Tropical cyclones is a daughter project of WikiProject meteorology. The dozens of semi-active members and several full-time members focus on improving Wikipedia's coverage of tropical cyclones.

WikiProject Non-tropical storms is a collaborative project to improve articles related to winter storms, wind storms, and extratropical cyclones.

Wikipedia is a fully collaborative effort by volunteers. So if you see something you think you can improve, be bold and get to editing! We appreciate any help you can provide!