Clear-Air Turbulence (often abbreviated CAT and sometimes colloquially referred to as "air pockets") is the erratic movement of air masses in the absence of any visual cues (such as clouds).
turbulence - 1. Irregular fluctuations occurring in fluid motions. It is characteristic of turbulence that the fluctuations occur in all three velocity components and are unpredictable in detail; however, ...
A state of fluid flow in which the instantaneous velocities exhibit irregular and apparently random fluctuations. Theses fluctuations are capable of transporting atmospheric properties.
Turkey tower ...
TURBULENCE: Disrupted flow in the atmosphere that produces gusts and eddies.
UKMET: United Kingdom forecast model.
UPWELLING: The rising of cold water from the deeper areas of the ocean to the surface. This phenomena often occurs along the California coast during the spring and summer.
The irregular, seemingly random movement of fluids such as the air and atmosphere.
Irregular motion of the atmosphere, as indicated by gusts and lulls in the wind.
Turkey Tower ...
(Turbulent Flow) Random and continuously changing air motion which are superposed on the mean motion of the air.
An intermediate period of illumination of the sky before sunrise and after sunset; there are three definitions of twilight: civil, nautical, and astronomical.
~ Any irregular or disturbed flow in the atmosphere that produces gusts and eddies.
Twilight The time immediately before sunrise and after sunset when the sky remain illuminated.
Typhoon A hurricane that forms in the western Pacific Ocean.
~ Irregular, apparently random motions of a fluid such as air or water.
~—In meteorology, any irregular or disturbed flow in the atmosphere.
The irregular and instantaneous motions of air which is made up of a number of small eddies that travel in the general air current. Atmospheric ~ is caused by random fluctuations in the wind flow.
~ - Random swirling of the air felt as gusts and bumps in flight.
TWIST - See WASHOUT
TWO-AXIS CONTROL - A control system consisting of only rudder and elevator or weight-shift and rudder.
~ - Aviation term for flight affected from flying through turbulent air. Often causes the aircraft to shake, but in extreme cases can upset (through out of control) and / or damage the aircraft.
CLEAR AIR ~
Name given to ~ that may occur in perfectly clear air without any visual in warning in the form of clouds.
~ that is similar to Light ~ but of greater intensity. Changes in altitude and/or attitude occur but the aircraft remains in positive control at all times. It usually causes variations in indicated airspeed, or ...
Clear air ~ (CAT) ~ encountered by aircraft flying through cloudless skies. Thermals, wind shear, and jet streams can each be a factor in producing CAT.
The region of ~ immediately to the rear of a solid body caused by the flow of air over or around the body.
NOAA National Weather Service - Cite This Source - This Definition
Browse Related Terms: Clear Air ~, Hygroscopic, Offshore Flow, Onshore Flow, outflow ...
Pilot Report (PIREP): A report of inflight weather by an aircraft pilot or crew member. A complete coded report includes the following information in this order: location and/or extent of reported weather phenomenon: type of aircraft (only with reports ~ or icing.
The vertical motion of the air, at times violent, which can cause the up-and-down movement of a plane.
The name given to hurricanes in the western North Pacific Ocean, west of the International Date Line.
The troposphere is characterized by decreasing temperature with height, and is the layer of the atmosphere containing the most clouds and other common weather phenomena.troughOn a weather chart, a narrow, elongated area of relatively low pressure.~An irregular motion of the ...
When observed at high levels (i.e., in cirrus formations), they may indicate severe or extreme ~.
It is available for every elevation angle sampled, it provides a measure of the variability of the mean radial velocity estimates due to wind shear, ~, and/or the quality of the velocity samples.
Clear-air ~ ~ encountered by aircraft when flying through air space devoid of clouds. Thermals and wind shear are the main causes. Clinometer An instrument for measuring angles of inclination. Used in conjunction with a ceiling light to measure cloud height at night.
At above 2 km altitude, the wind appears to be undisturbed by the surface, and ~ is slight. Empirical formulas have been given for the variation of velocity with height, such as v = khα with α = 1/5 or 1/4. The variation is greater for stronger winds.
These properties are interconnected by the various physical processes such as precipitation, evaporation, infrared radiation, convection, advection, and ~. climate change The long-term fluctuations in temperature, precipitation, wind, and all other aspects of the Earth's climate.
At the same time, the ~ in the cumulonimbus clouds creates positively and negatively electrically-charged areas within the clouds.
These are precipitation gauges designed to minimize ~ around the orifice, and are high enough above the ground to prevent most blowing snow from entering.
Troposphere-The lowest layer of the atmosphere marked by considerable ~ and a decrease in temperature with height. This layer stretches from the surface to approximately 10km. Weather on earth is created here.
Cirrus are composed of minute ice crystals, in regions where air temperature is lower than -20°C or -30°C. They may be caused by ~ and wind shear, or by upper-tropospheric convection.
Microscale - a study of small gusts, eddies and things that last less than an hour, usually. ~, diffusion, and wind shear are examples.
Millibar - an atmospheric pressure of 100 Pascals (Newtons per square metre).
air mass having static stability in its lower layers; it is free from convection, has a low degree of ~ and may have stratiform clouds or fog, or no clouds.
climatology and meteorology ...
The physics usually consists of advection, radiation calculations, surface fluxes (latent, sensible heat etc.), convection, ~ and clouds. More elaborate Earth System models often contain tracers related to atmospheric chemistry and aerosols (including dust and sea salt).
Eye wall: The ring of thunderstorms that surrounds a storm's eye. The heaviest rain, strongest winds and worst ~ are normally in the eye wall. ...
Microscale - A small-sized event that is usually measured in meters and seconds to minutes; a cloud-sized phenomenon; e.g. ~, and dust devils.
Vertical wind shear is mentioned most often: this is a change of the wind direction and/or speed with altitude. Strong vertical shear can cause ~ that affects aircraft and favors severe thunderstorm development when the atmosphere is unstable.
Actually this term has nothing to do with pet cats. It is used by British meteorologists to designate a warning to pilots about Clear Air ~, which is usually a cloud-free wind shear zone aloft that can make for a bumpy plane ride.
ALTOCUMULUS CASTELLANUS A middle cloud with vertical development that forms from altocumulus clouds. It is composed primarily of ice crystals in its higher portions and characterized by its turrets, protuberances, or crenelated tops. Its formation indicates instability and ~ at the ...
Furthermore, the wind convergence resulting from the southwesterly and the northeasterly trade winds often cause air ~ and whirlpool.
air within this branch has a high enough relative humidity that, upon lifting, the air parcel reaches saturation. Individual billow clouds generally have life times of a few minutes. The presence of billow clouds provides a visible signal to aviation interests of potentially dangerous ~.
The temperature differences across a cold front can be extreme and associated with strong winds. The warm tropical air is forced to rise and become unstable with the development of large cumuliform clouds. Severe weather such as thunderstorms, squall lines and severe ~ may accompany these ...
~A warning issued when sustained winds of 39 to 73 miles per hour (34 to 63 knots) are expected within 24 hours.TwisterA colloquial term for a tornado.TyphoonA hurricane that forms in the Western Pacific Ocean.
See also: What is the meaning of Cloud, Air, Surface, Temperature, Water?