Abbreviation for visual flight rules, but commonly used to refer to the relatively favorable weather and/or flight conditions to which these rules apply.

A radiosonde which transmits the indication of the meteorological sensing elements in the form of a code consisting of combinations of dots and dashes.

General name for an instrument which measures the earth's magnetic field intensity.

The record of an aneroid barograph.

A reflecting type telescope with a 45

A device for measuring the frequency of occurrence of atmospherics whose intensity is greater than a predetermined level.

See feed.

National Weather Service. Administered by the U.S. Department of Commerce.

Video Display Terminal. An input and display device which includes a keyboard and a screen and allows a human to communicate with a computer.

A thermometer consisting of a clock mechanism the speed of which is a function of temperature.

A type of precipitation composed of unbranched crystals in the form of needles, columns, or plates. Usually has a very slight downward motion and may fall from a cloudless sky.

Thermometer used for measuring the highest temperature attained during a given interval of time, for example, a day.

Same as contact anemometer.

A mercury barometer designed for use aboard ship. The instrument is of the fixed-cistern type (see Kew barometer). The mercury tube is constructed with a wide bore for its upper portion and with a capillary bore for its lower portion. This is done to incr ...

Part of a computer word that has meaning in itself, often, a byte.

A very sensitive electrostatic electrometer for measuring small potential differences.

A set of electrical conductors, often on a backplane, that carry data and power signals among the various components of a computer.

A type of cloud height indicator which uses a searchlight to project vertically a narrow beam of light onto the cloud base. The height of the cloud is determined using a clinometer, located at a known distance from the ceiling light, to measure the angle ...

A hypothetical "body" whose surface absorbs no electromagnetic radiation of any wavelength. An idealization exactly opposite to that of the black body. In nature, no true white bodies are known. Moist white pigments exhibiting high reflectivity for visibl ...

Difference between the instantaneous wind velocity at a point and the mean wind velocity taken over a given time interval. Also called fluctuation velocity.