Portal:Weather

The weather portal

Weather is the state of the atmosphere, describing for example the degree to which it is hot or cold, wet or dry, calm or stormy, clear or cloudy. 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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The 1933 Atlantic hurricane season was the second most active Atlantic hurricane season on record, with 21 storms forming during that year in the northwest Atlantic Ocean. The season ran through the summer and the first half of fall in 1933, and was only surpassed in total number of tropical cyclones by the 2005 season, which had 28 storms. The 1933 season saw tropical activity before its start, and a tropical cyclone was active for all but 13 days from June 28 to October 7. Tropical cyclones that did not approach populated areas or shipping lanes, especially if they were relatively weak and of short duration, may have remained undetected. Because technologies such as satellite monitoring were not available until the 1960s, historical data on tropical cyclones from this period are often not reliable. Compensating for the lack of comprehensive observation, one hurricane researcher estimates the season produced 24 tropical cyclones.

Ten of the season's 21 storms attained hurricane status. Five of those were major hurricanes, with sustained winds of over 111 miles per hour (179 km/h); the strongest reached peak winds of 150 miles per hour (240 km/h) near the Bahamas in early October. The season produced several deadly storms, with eight storms killing more than 20 people. All but one of the 21 known storms affected land at some point during their lifetimes.

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

... that MyRadar uses a custom satellite constellation to help forecast the weather?
... that state representative Karl Bohnak, referring to his former profession, said that the Upper Peninsula of Michigan was one of the most challenging places in the U.S. to forecast the weather?
... that the apricot dress of Jacqueline Kennedy kept its shape in India's hot weather?
... that Richard Davis made the earliest known continuous land-based weather recordings in New Zealand?
... that a Michigan TV station rescued and restored a weather ball that had been sitting for years in a scrapyard?
... that after Irish post office clerk Maureen Flavin Sweeney reported worsening weather conditions, Dwight D. Eisenhower agreed to postpone D-Day by 24 hours?

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Ground fog is a name given to fog that forms a shallow layer near the ground, sometimes just tens of centimeters thick. It can form due to warm air moving over a colder surface (advection fog), or at night due to the escape of thermal radiation into space (radiation fog). This scene is in Nordstemmen, Lower Saxony, Germany just after sunset.

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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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March 10

2019: A storm which had been wandering near the coast of Mozambique for a week strengthened and was given the name Cyclone Idai. The storm would drift in and around the Mozambique Channel for several days, bringing flooding rains and damaging winds and storm surge that would eventually kill more than 700 people in southern Africa.

March 11

2007: Cyclone Hamish dissipated off the coast of Queensland.

March 12

2006: The worst day of a multi-day outbreak of tornadoes struck the Midwestern and South Central United States, killing 9 people in Illinois and Missouri.

March 13

2019: An extratropical storm system began to rapidly intensify over Colorado, bringing blizzard conditions and wind gusts as high as 97 miles per hour (156 km/h) to the state. This storm would move eastward across the Central United States, eventually causing record flooding in several states due to heavy rains and melting snow.

March 14

1862: Vilhelm Bjerknes, known as one of the founding fathers of weather forecasting, was born in Christiana (now Oslo), Norway.

March 15

1889: The Apia cyclone wrecked or sunk six ships in the harbor of Apia, Samoa, killing at least 147 people.

March 16

1942: The Weather Prediction Center (then known as the Analysis Center) began operations in Washington, D.C.

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John Dalton FRS (/ˈdɔːltən/; 5 or 6 September 1766 – 27 July 1844) was an English chemist, physicist and meteorologist. He introduced the atomic theory into chemistry. He also researched colour blindness; as a result, the umbrella term for red-green congenital colour blindness disorders is Daltonism in several languages. (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!