A definite portion of a stream channel, commonly taken between two gauging stations, but may be taken between any two specified points.

Central Processing Unit. The part of a computer which controls and directs all functions.

A temperature scale with the ice point at 273 degrees and boiling point of water at 373 degrees. It is intended to approximate the Kelvin temperature scale with sufficient accuracy for many sciences, notably meteorology.

A device attached to a meteorological instrument to provide ventilation; usually a suction fan.

A relatively small-scale, upward moving current of air.

An instrument for the measurement of both solar and terrestrial radiation.

The total of all deviations of a transducer's output from a specified straight line in a constant environment.

The record of an aneroid barograph.

In folklore, a name for rain.

The maximum difference in output for any given input (within the specified range) when the value is approached first with increasing, and then with decreasing, input signals. Caused by energy absorption in the elements of the measuring instrument. Usually ...

Temperature of equilibrium between the liquid and vapor phases of a substance at a given pressure.

An evaluation, according to set procedures, of those weather elements which are most important for aircraft operations. Always includes cloud height or vertical visibility, sky cover, visibility, obstructions to vision, certain atmospheric phenomena, and ...

A small balloon, loaded with ballast and inflated so that it will explode at a predetermined altitude, which is attached to a larger balloon.

An instrument whose calibration is determined by comparison with an absolute instrument.

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

An instrument for measuring angles of inclination. Used in conjunction with a ceiling light to measure cloud height at night.

Same as ceiling light.

An instrument used to indicate wind direction.

A colloquial term in western Australia for a squall, associated with thunder, on the northwest coast in summer.

A balloon designed to float at a constant pressure level. This may be accomplished by a pressure valve which controls the release of ballast so as to maintain flight above a selected pressure level until the supply of ballast is exhausted. See Moby Dick b ...