Meteorology is a branch of the atmospheric sciences which includes atmospheric chemistry and atmospheric physics, with a major focus on weather forecasting. The study of meteorology dates back millennia, though significant progress in meteorology did not occur until the 18th century. The 19th century saw modest progress in the field after weather observation networks were formed across broad regions. Prior attempts at prediction of weather depended on historical data. It was not until after the elucidation of the laws of physics and more particularly, the development of the computer, allowing for the automated solution of a great many equations that model the weather, in the latter half of the 20th century that significant breakthroughs in weather forecasting were achieved. An important domain of weather forecasting is marine weather forecasting as it relates to maritime and coastal safety, in which weather effects also include atmospheric interactions with large bodies of water.
La Niña is an oceanic and atmospheric phenomenon that is the colder counterpart of El Niño, as part of the broader El Niño–Southern Oscillation (ENSO) climate pattern. The name La Niña originates from Spanish for "the little girl", by analogy to El Niño, meaning "the little boy". In the past, it was also called an anti-El Niño and El Viejo, meaning "the old man".
Climatology or climate science is the scientific study of climate, scientifically defined as weather conditions averaged over a period of time. This modern field of study is regarded as a branch of the atmospheric sciences and a subfield of physical geography, which is one of the Earth sciences. Climatology now includes aspects of oceanography and biogeochemistry.
The National Weather Service (NWS) is an agency of the United States federal government that is tasked with providing weather forecasts, warnings of hazardous weather, and other weather-related products to organizations and the public for the purposes of protection, safety, and general information. It is a part of the National Oceanic and Atmospheric Administration (NOAA) branch of the Department of Commerce, and is headquartered in Silver Spring, Maryland, within the Washington metropolitan area. The agency was known as the United States Weather Bureau from 1890 until it adopted its current name in 1970.
The Storm Prediction Center (SPC) is a government agency that is part of the National Centers for Environmental Prediction (NCEP), operating under the control of the National Weather Service (NWS), which in turn is part of the National Oceanic and Atmospheric Administration (NOAA) of the United States Department of Commerce (DoC).
The Weather Prediction Center (WPC), located in College Park, Maryland, is one of nine service centers under the umbrella of the National Centers for Environmental Prediction (NCEP), a part of the National Weather Service (NWS), which in turn is part of the National Oceanic and Atmospheric Administration (NOAA) of the U.S. Government. Until March 5, 2013 the Weather Prediction Center was known as the Hydrometeorological Prediction Center (HPC). The Weather Prediction Center serves as a center for quantitative precipitation forecasting, medium range forecasting, and the interpretation of numerical weather prediction computer models.
The climate of Virginia, a state on the east coast of the United States, is considered mild compared to other areas of the United States. Most of Virginia east of the Blue Ridge mountains, the southern part of the Shenandoah Valley, and the Roanoke Valley, has a humid subtropical climate. In the mountainous areas west of the Blue Ridge, the climate becomes warm-summer humid continental and oceanic climate. Severe weather, in the form of tornadoes, tropical cyclones, and winter storms, impacts the state on a regular basis. Central Virginia received significant snowfall of 20 inches in December 2009.
The Arctic oscillation (AO) or Northern Annular Mode/Northern Hemisphere Annular Mode (NAM) is a weather phenomenon at the Arctic poles north of 20 degrees latitude. It is an important mode of climate variability for the Northern Hemisphere. The southern hemisphere analogue is called the Antarctic oscillation or Southern Annular Mode (SAM). The index varies over time with no particular periodicity, and is characterized by non-seasonal sea-level pressure anomalies of one sign in the Arctic, balanced by anomalies of opposite sign centered at about 37–45° N.
The Environmental Modeling Center (EMC) is a United States Government agency, which improves numerical weather, marine and climate predictions at the National Centers for Environmental Prediction (NCEP), through a broad program of research in data assimilation and modeling. In support of the NCEP operational forecasting mission, the EMC develops, improves and monitors data assimilation systems and models of the atmosphere, ocean and coupled system, using advanced methods developed internally as well as cooperatively with scientists from universities, NOAA laboratories and other government agencies, and the international scientific community.
The Madden–Julian oscillation (MJO) is the largest element of the intraseasonal variability in the tropical atmosphere. It was discovered in 1971 by Roland Madden and Paul Julian of the American National Center for Atmospheric Research (NCAR). It is a large-scale coupling between atmospheric circulation and tropical deep atmospheric convection. Unlike a standing pattern like the El Niño–Southern Oscillation (ENSO), the Madden–Julian oscillation is a traveling pattern that propagates eastward, at approximately 4 to 8 m/s, through the atmosphere above the warm parts of the Indian and Pacific oceans. This overall circulation pattern manifests itself most clearly as anomalous rainfall.
This is a list of meteorology topics. The terms relate to meteorology, the interdisciplinary scientific study of the atmosphere that focuses on weather processes and forecasting.
The National Severe Storms Laboratory (NSSL) is a National Oceanic and Atmospheric Administration (NOAA) weather research laboratory under the Office of Oceanic and Atmospheric Research. It is one of seven NOAA Research Laboratories (RLs).
The National Weather Center (NWC), on the campus of the University of Oklahoma, is a confederation of federal, state, and academic organizations that work together to better understand events that take place in Earth's atmosphere over a wide range of time and space scales. The NWC partners give equal attention to applying that understanding to the development of improved observation, analysis, assimilation, display, and prediction systems. The National Weather Center also has expertise in local and regional climate, numerical modeling, hydrology, and weather radar. Members of the NWC work with a wide range of federal, state, and local government agencies to help reduce loss of life and property to hazardous weather, ensure wise use of water resources, and enhance agricultural production. They also work with private sector partners to develop new applications of weather and regional climate information that provide competitive advantage in the marketplace.
This article describes severe weather terminology used by the National Weather Service (NWS) in the United States. The NWS, a government agency operating as an arm of the National Oceanic and Atmospheric Administration (NOAA) branch of the United States Department of Commerce (DoC), defines precise meanings for nearly all of its weather terms.
Upper-atmospheric models are simulations of the Earth's atmosphere between 20 and 100 km that comprises the stratosphere, mesosphere, and the lower thermosphere. Whereas most climate models simulate a region of the Earth's atmosphere from the surface to the stratopause, there also exist numerical models which simulate the wind, temperature and composition of the Earth's tenuous upper atmosphere, from the mesosphere to the exosphere, including the ionosphere. This region is affected strongly by the 11 year Solar cycle through variations in solar UV/EUV/Xray radiation and solar wind leading to high latitude particle precipitation and aurora. It has been proposed that these phenomena may have an effect on the lower atmosphere, and should therefore be included in simulations of climate change. For this reason there has been a drive in recent years to create whole atmosphere models to investigate whether or not this is the case.
The Ocean Prediction Center (OPC), established in 1995, is one of the National Centers for Environmental Prediction's (NCEP's) original six service centers. Until 2003, the name of the organization was the Marine Prediction Center. Its origins are traced back to the sinking of the RMS Titanic in 1912. The OPC issues forecasts up to five days in advance for ocean areas north of 31° north latitude and west of 35° west longitude in the Atlantic, and across the northeast Pacific north of 30° north latitude and east of 160° east longitude. Until recently, the OPC provided forecast points for tropical cyclones north of 20° north latitude and east of the 60° west longitude to the National Hurricane Center. OPC is composed of two branches: the Ocean Forecast Branch and the Ocean Applications Branch.
The Climate Forecast System or coupled forecast system is a medium to long range numerical weather prediction and a climate model run by the National Centers for Environmental Prediction (NCEP) to bridge weather and climate timescales. Version 2 became operational as CFSv2 in 2011.
The Tuvalu Meteorological Service (TMS) is the principal meteorological observatory of Tuvalu and is responsible for providing weather services to the islands of Tuvalu. A meteorological office was established on Funafuti at the time the islands of Tuvalu were administered as parts of the Gilbert and Ellice Islands colony of the United Kingdom. The meteorological office is now an agency of the government of Tuvalu.
The National Centers for Environmental Information (NCEI), an agency of the United States government, manages one of the world's largest archives of atmospheric, coastal, geophysical, and oceanic data, containing information that ranges from the surface of the sun to Earth's core, and from ancient tree ring and ice core records to near-real-time satellite images.
The 2014–16 El Niño was a warming of the eastern equatorial Pacific Ocean that resulted in unusually warm waters developing between the coast of South America and the International Date Line. These unusually warm waters influenced the world's weather in a number of ways, which in turn significantly affected various parts of the world. These included drought conditions in Venezuela, Australia and a number of Pacific islands while significant flooding was also recorded. During the event, more tropical cyclones than normal occurred within the Pacific Ocean, while fewer than normal occurred in the Atlantic Ocean.
