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2013 Moore Tornado
On the afternoon of May 20, 2013, a large and extremely violent EF5 tornado ravaged through Moore, Oklahoma, and adjacent areas, with peak winds estimated at , killing 24 people (plus two indirect fatalities) and injuring 212 others. The tornado was part of a larger weather system that had produced several other tornadoes across the Great Plains over the previous two days, including five that struck portions of Central Oklahoma the day prior on May 19. The tornado touched down just northwest of Newcastle at 2:56 p.m. CDT (19:46 UTC), and stayed on the ground for 39 minutes over a path, crossing through a heavily populated section of Moore. The tornado was wide at its peak. It followed a roughly similar track to the deadlier 1999 Bridge Creek–Moore tornado, which was smaller in size but just as severe; however, very few homes and neither of the stricken schools in the area had purpose-built storm shelters in the intervening years since the earlier torn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
National Weather Service
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 NWS performs its primary task through a collection of national and regional centers, and 122 local Weather Forecast Offices (WFOs). As the NWS is an agency of the U.S. federal government, most of its products are in the public domain and available free of charge. History Calls for the creation of a government weather bureau began as early as 1844, when the electrical ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Agence France-Presse
Agence France-Presse (AFP) is a French international news agency headquartered in Paris, France. Founded in 1835 as Havas, it is the world's oldest news agency. AFP has regional headquarters in Nicosia, Montevideo, Hong Kong and Washington, D.C., and news bureaus in 151 countries in 201 locations. AFP transmits stories, videos, photos and graphics in French, English, Arabic, Portuguese, Spanish, and German. History Agence France-Presse has its origins in the Agence Havas, founded in 1835 in Paris by Charles-Louis Havas, making it the world's oldest news service. The agency pioneered the collection and dissemination of news as a commodity, and had established itself as a fully global concern by the late 19th century. Two Havas employees, Paul Julius Reuter and Bernhard Wolff, set up their own news agencies in London and Berlin respectively. In 1940, when German forces occupied France during World War II, the news agency was taken over by the authorities and renamed "Offi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atmospheric Instability
Atmospheric instability is a condition where the Earth's atmosphere is generally considered to be unstable and as a result the weather is subjected to a high degree of variability through distance and time. Atmospheric stability is a measure of the atmosphere's tendency to discourage or deter vertical motion, and vertical motion is directly correlated to different types of weather systems and their severity. In unstable conditions, a lifted thing, such as a parcel of air will be warmer than the surrounding air at altitude. Because it is warmer, it is less dense and is prone to further ascent. In meteorology, instability can be described by various indices such as the Bulk Richardson Number, lifted index, K-index, convective available potential energy (CAPE), the Showalter, and the Vertical totals. These indices, as well as atmospheric instability itself, involve temperature changes through the troposphere with height, or lapse rate. Effects of atmospheric instability in mois ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Air Mass
In meteorology, an air mass is a volume of air defined by its temperature and humidity. Air masses cover many hundreds or thousands of square miles, and adapt to the characteristics of the surface below them. They are classified according to latitude and their continental or maritime source regions. Colder air masses are termed polar or arctic, while warmer air masses are deemed tropical. Continental and superior air masses are dry, while maritime and monsoon air masses are moist. Weather fronts separate air masses with different density (temperature or moisture) characteristics. Once an air mass moves away from its source region, underlying vegetation and water bodies can quickly modify its character. Classification schemes tackle an air mass' characteristics, as well as modification. Classification and notation The Bergeron classification is the most widely accepted form of air mass classification, though others have produced more refined versions of this scheme over diffe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ozarks
The Ozarks, also known as the Ozark Mountains, Ozark Highlands or Ozark Plateau, is a physiographic region in the U.S. states of Missouri, Arkansas, Oklahoma and the extreme southeastern corner of Kansas. The Ozarks cover a significant portion of northern Arkansas and most of the southern half of Missouri, extending from Interstate 40 in central Arkansas to Interstate 70 in central Missouri. There are two mountain ranges in the Ozarks: the Boston Mountains of Arkansas and the St. Francois Mountains of Missouri. Buffalo Lookout, the highest point in the Ozarks, is located in the Boston Mountains. Geologically, the area is a broad dome with the exposed core in the ancient St. Francois Mountains. The Ozarks cover nearly , making it the most extensive highland region between the Appalachians and Rockies. Together with the Ouachita Mountains, the area is known as the U.S. Interior Highlands. The Salem Plateau, named after Salem, Missouri, makes up the largest geologic area o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rocky Mountains
The Rocky Mountains, also known as the Rockies, are a major mountain range and the largest mountain system in North America. The Rocky Mountains stretch in straight-line distance from the northernmost part of western Canada, to New Mexico in the southwestern United States. Depending on differing definitions between Canada and the U.S., its northern terminus is located either in northern British Columbia's Terminal Range south of the Liard River and east of the Trench, or in the northeastern foothills of the Brooks Range/ British Mountains that face the Beaufort Sea coasts between the Canning River and the Firth River across the Alaska-Yukon border. Its southernmost point is near the Albuquerque area adjacent to the Rio Grande rift and north of the Sandia–Manzano Mountain Range. Being the easternmost portion of the North American Cordillera, the Rockies are distinct from the tectonically younger Cascade Range and Sierra Nevada, which both lie farther to its we ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jet Stream
Jet streams are fast flowing, narrow, meandering air currents in the atmospheres of some planets, including Earth. On Earth, the main jet streams are located near the altitude of the tropopause and are westerly winds (flowing west to east). Jet streams may start, stop, split into two or more parts, combine into one stream, or flow in various directions including opposite to the direction of the remainder of the jet. Overview The strongest jet streams are the polar jets around the polar vortices, at above sea level, and the higher altitude and somewhat weaker subtropical jets at . The Northern Hemisphere and the Southern Hemisphere each have a polar jet and a subtropical jet. The northern hemisphere polar jet flows over the middle to northern latitudes of North America, Europe, and Asia and their intervening oceans, while the southern hemisphere polar jet mostly circles Antarctica, both all year round. Jet streams are the product of two factors: the atmospheric heating b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shortwave (meteorology)
A shortwave or shortwave trough is an embedded kink in the trough / ridge pattern. Its length scale is much smaller than that of and is embedded within longwaves, which are responsible for the largest scale (synoptic scale) weather systems. Shortwaves may be contained within or found ahead of longwaves and range from the mesoscale to the synoptic scale. Shortwaves are most frequently caused by either a cold pool or an upper level front. Shortwaves are commonly referred to as a vorticity maximum. Corresponding weather and effects Shortwaves are often associated with warm air advection (WAA) or cold air advection (CAA), which influence temperature. Due to the way they move the air around them and the way air moves away from them, shortwaves produce positive curvature vorticity and positive shear vorticity, respectively. Ahead of a shortwave there is large-scale lift due to divergence from positive vorticity advection (PVA). This lift often causes precipitation. In a cap ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Upper Midwest
The Upper Midwest is a region in the northern portion of the U.S. Census Bureau's Midwestern United States. It is largely a sub-region of the Midwest. Although the exact boundaries are not uniformly agreed-upon, the region is defined as referring to the states of Michigan, Minnesota and Wisconsin; some definitions include Iowa, North Dakota and South Dakota as well. Definitions The National Weather Service defines its Upper Midwest as the states of Iowa, Michigan, Minnesota, North Dakota, South Dakota and Wisconsin. The United States Geological Survey uses two different Upper Midwest regions: *The USGS Upper Midwest Environmental Sciences Center considers it to be the six states of Illinois, Indiana, Iowa, Michigan, Minnesota and Wisconsin, which comprise the watersheds of the Upper Mississippi River and upper Great Lakes. *The USGS Mineral Resources Program considers the area to contain Illinois, Indiana, Michigan, Minnesota and Wisconsin. The Association for Institutional Res ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The Dakotas
The Dakotas is a collective term for the U.S. states of North Dakota and South Dakota. It has been used historically to describe the Dakota Territory, and is still used for the collective heritage, culture, geography, fauna, sociology, economy, and cuisine among the two states. Etymology The name Dakota refers to the Dakota people. History The territory now known as the Dakotas includes a large portion of the ancestral land of Native American tribes, in particular various tribes of Sioux such as the Dakota people, also known as the Santee Sioux. The United States government stakes its claim to the land through the Louisiana Purchase and Rupert's Land accusation. The region historically involved a complex series of conflicts between the US government and Native American tribes (and among themselves). For a while the region consisted of the Minnesota and Nebraska territories until in 1861, the US government formed the Dakota Territory, which included both the modern states ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Low-pressure Area
In meteorology, a low-pressure area, low area or low is a region where the atmospheric pressure is lower than that of surrounding locations. Low-pressure areas are commonly associated with inclement weather (such as cloudy, windy, with possible rain or storms), while high-pressure areas are associated with lighter winds and clear skies. Winds circle anti-clockwise around lows in the northern hemisphere, and clockwise in the southern hemisphere, due to opposing Coriolis forces. Low-pressure systems form under areas of wind divergence that occur in the upper levels of the atmosphere (aloft). The formation process of a low-pressure area is known as cyclogenesis. In meteorology, atmospheric divergence aloft occurs in two kinds of places: * The first is in the area on the east side of upper troughs, which form half of a Rossby wave within the Westerlies (a trough with large wavelength that extends through the troposphere). * A second is an area where wind divergence aloft occu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Central United States
The Central United States is sometimes conceived as between the Eastern and Western as part of a three-region model, roughly coincident with the U.S. Census' definition of the Midwestern United States plus the western and central portions of the U.S. Census' definition of the Southern United States. The Central States are typically considered to consist of North Dakota, South Dakota, Nebraska, Kansas, Oklahoma, Texas, Minnesota, Iowa, Missouri, Arkansas, Louisiana, Wisconsin, Illinois, Michigan, Indiana, Ohio, Kentucky, Tennessee, West Virginia, Mississippi and Alabama. Chicago is the area's largest city and metropolitan area; other large cities with large metropolitan areas would be Houston, Dallas, Fort Worth, San Antonio, Austin, Oklahoma City, Tulsa, Kansas City, Kansas and Kansas City, Missouri, Topeka, Wichita, Omaha, Nebraska and Lincoln, Minneapolis and St. Paul, Madison and Milwaukee, St. Louis, Louisville, Lexington, Detroit, Cinci ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
