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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Did you know...
...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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Recent and ongoing weather
- Wikinews weather portal
- March 26, 2021: Tropical moisture ceases to cause severe floods in South East Australia
- February 19, 2021: Winter storms hammer Texas, fatalities reported
- December 28, 2021: Typhoon Phanfone strikes Philippines
- February 1, 2022: Deadly floods in Brazil after heavy rainfall
- April 15, 2022: South African floods kill at least 300 people
- Weather of 2024
- 2024 Atlantic hurricane season
- 2020–21 North American winter
- 2024 Pacific typhoon season
- Tornadoes of 2024
Related portals
This week in weather history...
January 14
1888: The severe cold wave associated with the blizzard two days earlier reached its peak. The temperature reached −65 °F at Fort Keogh in Montana, the second lowest temperature ever recorded in the Contiguous United States.
January 16
1362: Grote Mandrenke, Dutch for "Great Drowning of Men", produced an unprecedented storm tide in the Netherlands, killing 25,000 or more people.
January 17
1977: Snow is reported for the first time in West Palm Beach, Miami, and as far south as Homestead, Florida.
January 21
1918: The Mackay cyclone, levelled the city of Mackay, Queensland.
January 24
1967: A rare winter tornado outbreak affected the area around Saint Louis, Missouri, killing 3 people. The next day, thunderstorms produced sleet, freezing rain, and snow in the same areas.
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Weather lists
- List of cloud types
- List of meteorological phenomena
- List of meteorology institutions
- List of SPC High Risk days
- List of tornadoes and tornado outbreaks
- List of North American tornadoes and tornado outbreaks
- List of European tornadoes and tornado outbreaks
- List of Asian tornadoes and tornado outbreaks
- List of Southern Hemisphere tornadoes and tornado outbreaks
- List of F5 and EF5 tornadoes
- List of tornado-related deaths at schools
- List of tornadoes striking downtown areas
- List of tornado records
- List of New York hurricanes
- List of weather-related fatalities in the United States
- History of tropical cyclone spawned tornadoes
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!
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