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Tornado Outbreak Of February 7, 2017
A small but damaging outbreak of 15 tornadoes impacted the Southeast on February 7, 2017. The most damaging tornado of the outbreak was a large and powerful EF3 tornado. The tornado caused considerable damage along its path and left approximately 10,000 homes without electricity. 33 injuries occurred in the area after the tornado hit near Chef Menteur Highway with hundreds of structures sustaining moderate to significant damage along the ten-mile path. In response to the disaster, Governor John Bel Edwards declared a state of emergency. Other destructive and strong tornadoes occurred on this day as well, including an EF1 tornado that killed a man near Donaldsonville, Louisiana and another EF3 tornado that injured three and caused considerable damage to homes, trees, and power lines in Livingston Parish, Louisiana. Overall, the outbreak killed one and injured 40. Meteorological synopsis On February 4, the Storm Prediction Center (SPC) outlined a severe weather threat are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tornadoes Of 2017
This page documents notable tornadoes and tornado outbreaks worldwide in 2017. Strong and destructive tornadoes form most frequently in the United States, Brazil, Bangladesh, and East India, Eastern India, but they can occur almost anywhere under the right conditions. Tornadoes also develop occasionally in southern Canada during the Northern Hemisphere's summer and somewhat regularly at other times of the year across Europe, Asia, Argentina and Australia. Tornadic events are often accompanied with other forms of severe weather, including strong thunderstorms, strong winds, and hail. There were 1,522 reports of tornadoes in the United States in 2017, of which 1,418 were confirmed. Worldwide, 43 fatalities were confirmed in 2017: 35 in the United States, five in China, two in Paraguay, and one in Brazil. The tornado season in 2017 started exceptionally early, having the second most active January since records began in 1950, and one of the most active first quarters in recorded hist ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
New Orleans, Louisiana
New Orleans ( , ,New Orleans Merriam-Webster. ; french: La Nouvelle-Orléans , es, Nueva Orleans) is a Consolidated city-county, consolidated city-parish located along the Mississippi River in the southeastern region of the U.S. state of Louisiana. With a population of 383,997 according to the 2020 U.S. census, it is the List of municipalities in Louisiana, most populous city in Louisiana and the twelfth-most populous city in the southeastern United States. Serving as a List of ports in the United States, major port, New Orleans is considered an economic and commercial hub for the broader Gulf Coast of the United States, Gulf Coast region of the United States. New Orleans is world-renowned for its Music of New Orleans, distinctive music, Louisiana Creole cuisine, Creole cuisine, New Orleans English, uniq ... [...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 capped ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Slayden, Tennessee
Slayden is a town in Dickson County, Tennessee, United States. The population was 178 at the 2010 census. Geography Slayden is located in northwestern Dickson County at (36.294208, -87.470514). Tennessee State Route 235 passes through the town, leading northeast to Cunningham and south to Dickson. According to the United States Census Bureau, Slayden has a total area of , all land. Demographics As of the census of 2000, there were 185 people, 79 households, and 54 families residing in the town. The population density was 341.7 people per square mile (132.3/km2). There were 86 housing units at an average density of 158.9 per square mile (61.5/km2). The racial makeup of the town was 97.30% White, 0.54% African American, 1.62% Native American, and 0.54% from two or more races. There were 79 households, of which 25.3% had children under the age of 18 living with them, 59.5% were married couples living together, 5.1% had a female householder with no husband present, and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enhanced Fujita Scale
The Enhanced Fujita scale (abbreviated as EF-Scale) rates tornado intensity based on the severity of the damage they cause. It is used in some countries, including the United States, Canada, China, and Mongolia. The Enhanced Fujita scale replaced the decommissioned Fujita scale that was introduced in 1971 by Ted Fujita. Operational use began in the United States on February 1, 2007, followed by Canada on April 1, 2013. It has also been proposed for use in France. The scale has the same basic design as the original Fujita scale—six intensity categories from zero to five, representing increasing degrees of damage. It was revised to reflect better examinations of tornado damage surveys, in order to align wind speeds more closely with associated storm damage. Better standardizing and elucidating what was previously subjective and ambiguous, it also adds more types of structures and vegetation, expands degrees of damage, and better accounts for variables such as differences in con ... [...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] |
Time Zone
A time zone is an area which observes a uniform standard time for legal, Commerce, commercial and social purposes. Time zones tend to follow the boundaries between Country, countries and their Administrative division, subdivisions instead of strictly following longitude, because it is convenient for areas in frequent communication to keep the same time. All time zones are defined as offsets from Coordinated Universal Time (UTC), ranging from UTC−12:00 to UTC+14:00. The UTC offset, offsets are usually a whole number of hours, but a few zones are offset by an additional 30 or 45 minutes, such as in Indian Standard Time, India, Time in Australia, South Australia and Nepal Time, Nepal. Some areas of higher latitude use daylight saving time for about half of the year, typically by adding one hour to local time during spring (season), spring and summer. List of UTC offsets In the table below, the locations that use daylight saving time (DST) are listed in their UTC offse ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lapse Rate
The lapse rate is the rate at which an atmospheric variable, normally temperature in Earth's atmosphere, falls with altitude. ''Lapse rate'' arises from the word ''lapse'', in the sense of a gradual fall. In dry air, the adiabatic lapse rate is 9.8 °C/km (5.4 °F per 1,000 ft). It corresponds to the vertical component of the spatial gradient of temperature. Although this concept is most often applied to the Earth's troposphere, it can be extended to any gravitationally supported parcel of gas. Definition A formal definition from the ''Glossary of Meteorology'' is: :The decrease of an atmospheric variable with height, the variable being temperature unless otherwise specified. Typically, the lapse rate is the negative of the rate of temperature change with altitude change: :\Gamma = -\frac where \Gamma (sometimes L) is the lapse rate given in units of temperature divided by units of altitude, ''T'' is temperature, and ''z'' is altitude. Convection and adiabatic expansion ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrodynamical Helicity
:''This page is about helicity in fluid dynamics. For helicity of magnetic fields, see magnetic helicity. For helicity in particle physics, see helicity (particle physics).'' In fluid dynamics, helicity is, under appropriate conditions, an invariant of the Euler equations of fluid flow, having a topological interpretation as a measure of linkage and/or knottedness of vortex lines in the flow. This was first proved by Jean-Jacques Moreau in 1961 and Moffatt derived it in 1969 without the knowledge of Moreau's paper. This helicity invariant is an extension of Woltjer's theorem for magnetic helicity. Let \mathbf(x,t) be the velocity field and \nabla\times\mathbf the corresponding vorticity field. Under the following three conditions, the vortex lines are transported with (or 'frozen in') the flow: (i) the fluid is inviscid; (ii) either the flow is incompressible (\nabla\cdot\mathbf = 0), or it is compressible with a barotropic relation p = p(\rho) between pressure p and density \rh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wind Shear
Wind shear (or windshear), sometimes referred to as wind gradient, is a difference in wind speed and/or direction over a relatively short distance in the atmosphere. Atmospheric wind shear is normally described as either vertical or horizontal wind shear. Vertical wind shear is a change in wind speed or direction with a change in altitude. Horizontal wind shear is a change in wind speed with a change in lateral position for a given altitude. Wind shear is a microscale meteorological phenomenon occurring over a very small distance, but it can be associated with mesoscale or synoptic scale weather features such as squall lines and cold fronts. It is commonly observed near microbursts and downbursts caused by thunderstorms, fronts, areas of locally higher low-level winds referred to as low-level jets, near mountains, radiation inversions that occur due to clear skies and calm winds, buildings, wind turbines, and sailboats. Wind shear has significant effects on the control of a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hodograph
A hodograph is a diagram that gives a vectorial visual representation of the movement of a body or a fluid. It is the locus of one end of a variable vector, with the other end fixed. The position of any plotted data on such a diagram is proportional to the velocity of the moving particle. It is also called a velocity diagram. It appears to have been used by James Bradley, but its practical development is mainly from Sir William Rowan Hamilton, who published an account of it in the ''Proceedings of the Royal Irish Academy'' in 1846. Applications It is used in physics, astronomy, solid and fluid mechanics to plot deformation of material, motion of planets or any other data that involves the velocities of different parts of a body. See Swinging Atwood's machine Meteorology In meteorology, hodographs are used to plot winds from soundings of the Earth's atmosphere. It is a polar diagram where wind direction is indicated by the angle from the center axis and its strength by the di ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Convective Available Potential Energy
In meteorology, convective available potential energy (commonly abbreviated as CAPE), is the integrated amount of work that the upward (positive) buoyancy force would perform on a given mass of air (called an air parcel) if it rose vertically through the entire atmosphere. Positive CAPE will cause the air parcel to rise, while negative CAPE will cause the air parcel to sink. Nonzero CAPE is an indicator of atmospheric instability in any given atmospheric sounding, a necessary condition for the development of cumulus and cumulonimbus clouds with attendant severe weather hazards. Mechanics CAPE exists within the conditionally unstable layer of the troposphere, the free convective layer (FCL), where an ascending air parcel is warmer than the ambient air. CAPE is measured in joules per kilogram of air (J/kg). Any value greater than 0 J/kg indicates instability and an increasing possibility of thunderstorms and hail. Generic CAPE is calculated by integrating vertically the loc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
