Hurricane Danny (2015)
Hurricane Danny was the first major hurricane to develop between the Lesser Antilles and Western Africa since Hurricane Julia in 2010. The fourth tropical cyclone, and first hurricane of the 2015 Atlantic hurricane season, Danny originated from a well-defined tropical wave that emerged over the Atlantic Ocean on August 14. Traveling west, the system gradually coalesced into a tropical depression by August 18. After becoming a tropical storm later that day, dry air slowed further development. On August 20–21, dry air became removed from the system, and Danny rapidly intensified into a Category 3 hurricane on the Saffir–Simpson hurricane wind scale. Its peak was short-lived as wind shear soon increased and prompted significant weakening. Degrading to a tropical storm by August 23, Danny approached the Lesser Antilles. It degenerated into a tropical wave as it traversed the archipelago on August 24 and was last noted over Hispaniola the following day. Th ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Lesser Antilles
The Lesser Antilles ( es, link=no, Antillas Menores; french: link=no, Petites Antilles; pap, Antias Menor; nl, Kleine Antillen) are a group of islands in the Caribbean Sea. Most of them are part of a long, partially volcanic island arc between the Greater Antilles to the north-west and the continent of South America."West Indies." ''Merriam-Webster's Geographical Dictionary'', 3rd ed. 2001. () Springfield, MA: Merriam-Webster Inc., p. 1298. The islands of the Lesser Antilles form the eastern boundary of the Caribbean Sea where it meets the Atlantic Ocean. Together, the Lesser Antilles and the Greater Antilles make up the Antilles. (Somewhat confusingly, the word Caribbean is sometimes used to refer only to the Antilles, and sometimes used to refer to a much larger region.) The Lesser and Greater Antilles, together with the Lucayan Archipelago, are collectively known as the West Indies. History after European arrival The Spanish were the first Europeans to arrive on the ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
United States Virgin Islands
The United States Virgin Islands,. Also called the ''American Virgin Islands'' and the ''U.S. Virgin Islands''. officially the Virgin Islands of the United States, are a group of Caribbean islands and an unincorporated and organized territory of the United States. The islands are geographically part of the Virgin Islands archipelago and are located in the Leeward Islands of the Lesser Antilles to the east of Puerto Rico and west of the British Virgin Islands. The U.S. Virgin Islands consist of the main islands of Saint Croix, Saint John, and Saint Thomas and 50 other surrounding minor islands and cays. The total land area of the territory is . The territory's capital is Charlotte Amalie on the island of St. Thomas. Previously known as the Danish West Indies of the Kingdom of Denmark–Norway (from 1754 to 1814) and the independent Kingdom of Denmark (from 1814 to 1917), they were sold to the United States by Denmark for $25,000,000 in the 1917 Treaty of the Danish We ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Praia
Praia (, Portuguese language, Portuguese for "beach") is the capital and largest city of Cape Verde.Cape Verde, Statistical Yearbook 2015 Instituto Nacional de Estatística (Cape Verde), Instituto Nacional de Estatística Located on the southern coast of Santiago, Cape Verde, Santiago island, within the Sotavento Islands group, the city is the seat of the Praia, Cape Verde (municipality), Praia Municipality. Praia is the economic, political, and cultural center of Cape Verde. History The island of Santiago was discovered by António da Noli in 1460.[...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Coordinated Universal Time
Coordinated Universal Time or UTC is the primary time standard by which the world regulates clocks and time. It is within about one second of mean solar time (such as UT1) at 0° longitude (at the IERS Reference Meridian as the currently used prime meridian) and is not adjusted for daylight saving time. It is effectively a successor to Greenwich Mean Time (GMT). The coordination of time and frequency transmissions around the world began on 1 January 1960. UTC was first officially adopted as CCIR Recommendation 374, ''Standard-Frequency and Time-Signal Emissions'', in 1963, but the official abbreviation of UTC and the official English name of Coordinated Universal Time (along with the French equivalent) were not adopted until 1967. The system has been adjusted several times, including a brief period during which the time-coordination radio signals broadcast both UTC and "Stepped Atomic Time (SAT)" before a new UTC was adopted in 1970 and implemented in 1972. This change also a ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Atmospheric Convection
Atmospheric convection is the result of a parcel-environment instability, or temperature difference layer in the atmosphere. Different lapse rates within dry and moist air masses lead to instability. Mixing of air during the day which expands the height of the planetary boundary layer leads to increased winds, cumulus cloud development, and decreased surface dew points. Moist convection leads to thunderstorm development, which is often responsible for severe weather throughout the world. Special threats from thunderstorms include hail, downbursts, and tornadoes. Overview There are a few general archetypes of atmospheric instability that are used to explain convection (or lack thereof). A necessary (but not sufficient) condition for convection is that the environmental lapse rate (the rate of decrease of temperature with height) is steeper than the lapse rate experienced by a rising parcel of air. When this condition is met, upward-displaced air parcels can become buoyant and th ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Subtropical Ridge
The horse latitudes are the latitudes about 30 degrees north and south of the Equator. They are characterized by sunny skies, calm winds, and very little precipitation. They are also known as Subtropics, subtropical ridges, or highs. It is a high-pressure area at the divergence of trade winds and the westerlies. Origin of the term A likely and documented explanation is that the term is derived from the "dead horse" ritual of seamen (see Flogging a dead horse#Earlier meaning, Beating a dead horse). In this practice, the seaman paraded a straw-stuffed effigy of a horse around the deck before throwing it overboard. Seamen were paid partly in advance before a long voyage, and they frequently spent their pay all at once, resulting in a period of time without income. If they got advances from the ship's paymaster, they would incur debt. This period was called the "dead horse" time, and it usually lasted a month or two. The seaman's ceremony was to celebrate having worked off the "d ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Deformation (meteorology)
Deformation is the rate of change of shape of fluid bodies. Meteorologically, this quantity is very important in the formation of atmospheric fronts, in the explanation of cloud shapes, and in the diffusion of materials and properties.Djurić, D: "Weather Analysis". Prentice Hall, 1994. . Equations The deformation of horizontal wind is defined as \operatorname \mathbf = \sqrt, where \ A = \frac + \frac and \ B = \frac - \frac, representing the derivatives of wind component. Because these derivatives vary greatly with the rotation of the coordinate system, so do \ A and \ B. Stretching direction The deformation elements \ A and \ B (above) can be used to find the ''direction of the dilatation axis'', the line along which the material elements stretch (also known as the ''stretching direction''). Several flow patterns are characteristic of large deformation: confluence, diffluence, and shear flow. , also known as ''stretching'', is the elongating of a fluid body along the flow ( ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Sea Surface Temperature
Sea surface temperature (SST), or ocean surface temperature, is the ocean temperature close to the surface. The exact meaning of ''surface'' varies according to the measurement method used, but it is between and below the sea surface. Air masses in the Earth's atmosphere are highly modified by sea surface temperatures within a short distance of the shore. Localized areas of heavy snow can form in bands downwind of warm water bodies within an otherwise cold air mass. Warm sea surface temperatures are known to be a cause of tropical cyclogenesis over the Earth's oceans. Tropical cyclones can also cause a cool wake, due to turbulent mixing of the upper of the ocean. SST changes diurnally, like the air above it, but to a lesser degree. There is less SST variation on breezy days than on calm days. In addition, ocean currents such as the Atlantic Multidecadal Oscillation (AMO), can affect SST's on multi-decadal time scales, a major impact results from the global thermohaline ci ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Tropical Cyclogenesis
Tropical cyclogenesis is the development and strengthening of a tropical cyclone in the atmosphere. The mechanisms through which tropical cyclogenesis occurs are distinctly different from those through which temperate cyclogenesis occurs. Tropical cyclogenesis involves the development of a warm-core cyclone, due to significant convection in a favorable atmospheric environment. Tropical cyclogenesis requires six main factors: sufficiently warm sea surface temperatures (at least ), atmospheric instability, high humidity in the lower to middle levels of the troposphere, enough Coriolis force to develop a low-pressure center, a pre-existing low-level focus or disturbance, and low vertical wind shear. Tropical cyclones tend to develop during the summer, but have been noted in nearly every month in most basins. Climate cycles such as ENSO and the Madden–Julian oscillation modulate the timing and frequency of tropical cyclone development. There is a limit on tropical cyclone i ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Monsoon
A monsoon () is traditionally a seasonal reversing wind accompanied by corresponding changes in precipitation but is now used to describe seasonal changes in atmospheric circulation and precipitation associated with annual latitudinal oscillation of the Intertropical Convergence Zone (ITCZ) between its limits to the north and south of the equator. Usually, the term monsoon is used to refer to the rainy phase of a seasonally changing pattern, although technically there is also a dry phase. The term is also sometimes used to describe locally heavy but short-term rains. The major monsoon systems of the world consist of the West African, Asia–Australian, the North American, and South American monsoons. The term was first used in English in British India and neighboring countries to refer to the big seasonal winds blowing from the Bay of Bengal and Arabian Sea in the southwest bringing heavy rainfall to the area. Etymology The etymology of the word monsoon is not wholl ... [...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 force, Coriolis forces. Low-pressure systems form under areas of wind divergence that occur in the upper levels of the Atmosphere of Earth, atmosphere (aloft). The formation process of a low-pressure area is known as cyclogenesis. In Meteorology#Dynamic meteorology, meteorology, atmospheric divergence aloft occurs in two kinds of places: * The first is in the area on the east side of upper Trough (meteorology), troughs, which form half of a Rossby wave within the Westerlies (a trough (meteorology), trough with la ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
National Hurricane Center
The National Hurricane Center (NHC) is the division of the United States' NOAA/National Weather Service responsible for tracking and predicting tropical weather systems between the Prime Meridian and the 140th meridian west poleward to the 30th parallel north in the northeast Pacific Ocean and the 31st parallel north in the northern Atlantic Ocean. The agency, which is co-located with the Miami branch of the National Weather Service, is situated on the campus of Florida International University in Westchester, Florida. The NHC's Tropical Analysis and Forecast Branch (TAFB) routinely issues marine forecasts, in the form of graphics and high seas forecasts year round, with the Ocean Prediction Center having backup responsibility for this unit. The Technology and Science Branch (TSB) provides technical support for the center, which includes new infusions of technology from abroad. The Chief, Aerial Reconnaissance Coordination, All Hurricanes (CARCAH) unit tasks planes, for r ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |