Meteorology
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WordDefinitionEnglishAmerican
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Advectionthe movement of air in a horizontal direction
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Advection fogfog which forms when warmer
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Airmassa very large mass of air in the atmosphere in which the temperature is almost constant and which is divided from another mass by a front
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Anabaticreferring to a warm flow of air travel¬ling up a hillside or mountainside
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Anabatic winda wind current, caused by solar heating of the land, that rises up a southfacing mountainside
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AnafrontA front at which the warm air is ascending the frontal surface up to high altitudes
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AnticyclogenesisDevelopment or intensification of a high-pressure center
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Anvil clouda cloud, usually a large dark thundercloud, which has the shape of an anvil
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Anvil crawlerA lightning discharge occurring within the anvil of a thunderstorm, characterized by one or more channels that appear to crawl along the underside of the anvil
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Atmospherea mixture of gases in a mass surrounding the earth
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WordDefinitionEnglishAmerican
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Beaufort scalescale from 1 to12 used to refer to the strength of wind
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WordDefinitionEnglishAmerican
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Clouda mass of water vapour or ice particles in the sky that can produce rain
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Cloud basethe bottom part of a layer of cloud
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Cloud ceilingthe height above the ground or water of the base of the lowest layer of cloud
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Cloud groupa collection of different cloud types which have similarities
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Cold frontan advancing mass of cold air, moving under and lifting warmer air
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Convectionthe process by which hot air rises and cool air descends
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Convective cloudsclouds formed as a result of warm moist air rising and condensing at altitude
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Convergencethe fact of coming together at a particular point
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Coolweather which is not hot, warm nor very cold
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Cyclonea system of winds rotating inwards to an area of low barometric pressure
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WordDefinitionEnglishAmerican
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Depressionan area of low atmospheric pressure
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Dew pointthe temperature at which air is saturated with water vapour and condensation begins
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Diurnal variationIn meteorology, refers to the daily pattern of winds and temperatures
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DownburstA strong downward rush of air which produces a blast of damaging wind on or close to the surface
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Dust devilsA small but rapidly rotating column of wind of short duration that is made visible by dust, sand, and debris picked up from the ground
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Dust WhirlA rotating column of air rendered visible by dust
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WordDefinitionEnglishAmerican
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Fogcondensed water vapour in cloud-like masses lying close to the ground and limiting visibility
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Frontthe forward part or surface. The line that separates warm and cold front
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Frontal depressionan area of low pressure found together with a weather front
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Frontal systema series of rain-bearing changes in the weather
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Frosta deposit of very small ice crystals formed when water vapour condenses at a temperature below freezing
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WordDefinitionEnglishAmerican
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Galea very strong wind usually blowing from a single direction
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Gradiantthe rate at which a quantity such as temperature or pressure changes relative to change in a given variable, especially distance
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Gusta strong, sudden rush of wind
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WordDefinitionEnglishAmerican
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Hailprecipitation as small pellets of ice
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Hailstorma storm, where the precipitation is hail instead of rain or snow
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Hazedust or smoke in the atmosphere
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Humiditya measurement of how much water vapour is contained in the air
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WordDefinitionEnglishAmerican
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Icefrozen water
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InstabilityThe tendency for air parcels to accelerate when they are displaced from their original position
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Inversionan atmospheric phenomenon where cold air is nearer the ground than warm air
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Isobara line on a weather chart joining points of equal atmospheric pressure
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Isobaricreferring to or showing isobars
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WordDefinitionEnglishAmerican
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Jet streama band of strong winds at high altitude
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WordDefinitionEnglishAmerican
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Katabaticreferring to a cold flow of air travelling down hillsides or mountainsides
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Katabatic winda wind which occurs when the air in contact with the slope of a hill is cooled to a temperature lower than that in the free atmosphere, causing it to sink
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Knota unit of speed equal to one nautical mile per hour, approximately 1.85 kilometres or 1.15 statute miles per hour
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WordDefinitionEnglishAmerican
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Lightninga powerful and sudden electrical discharge from a cloud
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Lightning strikethe hitting of something by a discharge of lightning
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WordDefinitionEnglishAmerican
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Maritime winda wind blowing from the sea
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METARaviation routine weather report
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Meteorological charta chart of part of the Earth’s surface with information about weather conditions
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Meteorological conditionsa description of the weather in a given area
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Meteorologya science which studies weather and weather conditions
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Microbursta particularly strong windshear especially associated with thunderstorms
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Mistvisible water vapour, in the form of very fine droplets, in the atmosphere
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WordDefinitionEnglishAmerican
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Occluded fronta weather front created when air is forced upward from the Earth’s surface, as when a cold front overtakes and undercuts a warm front
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Occlusionthe forcing of air upward from the Earth’s surface, as when a cold front overtakes and undercuts a warm front
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WordDefinitionEnglishAmerican
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Precipitationwater falling as rain, drizzle, hail, sleet and snow from the atmosphere onto the surface of the Earth
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Pressureforce applied uniformly over a surface, measured as force per unit of area
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WordDefinitionEnglishAmerican
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Rainprecipitation or water which falls from clouds in small drops
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Rainstormheavy rain accompanied by wind
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Relative humiditythe ratio between the amount of water vapour in the air and the amount which would be present if the air was saturated, at the same temperature and the same pressure
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Ridgea long zone of relatively high atmospheric pressure
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Rime iceice formed when individual droplets of water freeze rapidly on striking the aircraft surface
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Roll cloudcloud created in the rotor zone on the downwind side of mountain ranges
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WordDefinitionEnglishAmerican
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Showera short period of rain or snow
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Sleetmelting snow or a mixture of rain and snow falling together
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Snowatmospheric water vapour frozen into ice crystals and falling to Earth as white flakes
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Snowfalla quantity of snow which comes down at any one time
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Snowflakea small piece of snow formed from a number of ice crystals
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Snowstorma heavy fall of snow accompanied by wind
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Squalla sudden increase in wind speed lasting for several minutes
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Stable AirAir that is colder than its surroundings and as such is resistant to upward movement
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Storma violent weather disturbance with high winds and rain or snow
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Sublimationtransformation directly from the solid to the gaseous state or from the gaseous to the solid state without becoming a liquid
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WordDefinitionEnglishAmerican
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Temperaturea measurement, in degrees, of the intensity of heat of a body
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Thunderthe noise created by the violent expansion and contraction of air momentarily heated by a lightning discharge
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Thunderstorma violent weather condition in which wind speeds increase, rain or hail falls and there is lightning activity
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Tornadoa violent storm of small extent, with rotating winds
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Tropical storma violent wind system which forms over tropical oceans
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Tropopausethe level at which the troposphere and the stratosphere meet
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Turbulencean irregular motion of the atmosphere
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WordDefinitionEnglishAmerican
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Updraughta rising current of air
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WordDefinitionEnglishAmerican
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Vapourthe gaseous form of a liquid
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Visibilitythe ability to see unlighted objects by day and lighted objects by night, subject to atmospheric conditions
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Vortexcyclonic flow in a relative small area
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WordDefinitionEnglishAmerican
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Warm frontan advancing mass of warm air moving over a mass of cooler air
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Windhorizontal movement of air in relation to the Earths surface
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Wind directiona natural movement of air at a velocity relative to the surface of earth
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Windsheara change in wind direction and speed between slightly different altitudes