Situated on the side from which the wind blows.

The mean difference between the readings of a given instrument and those of a standard instrument.

General term for an instrument used to make direct measurements of visual range or measurements of the physical characteristics of the atmosphere which determine the visible range.

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

Abbreviation for radio frequency.

Similar to the spectroheliograph, but used for visual instead of photographic purposes.

A wave resulting from the action of wind on a water surface.

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

An instrument used to measure the water vapor content of the air.

A pressure-plate anemometer consisting of a plate which is free to swing about a horizontal axis in its own plane above its center of gravity. The angular deflection of the plate is a function of the wind speed. This instrument is not used for station mea ...

A unit of energy equal to 101 ergs or to 0.2389 calories.

An aneroid barometer with a scale graduated in altitude instead of pressure units.

A protocol similar to RS232 which permits data interchange on multidrop networks of up to 32 nodes using a single twisted pair cable. In order for this protocol to be used, each device on a network must have some level of intelligence in order establish o ...

A medium-sized instrument shelter. It is a white louvered box with a flat double to of and is mounted four feet above the ground on a four-legged stand.

A method of winds aloft observation accomplished by tracking a balloon-borne radar target or radiosonde with either radar or a radio theodolite.

The volume of water required to cover one acre to a depth of one foot: 43,560 cubic feet.

The elevation of the water surface in a stream as measured by a river gauge with reference to some arbitrarily selected zero datum.

The pressure exerted by the atmosphere as a consequence of gravitational attraction exerted upon the "column" of air lying directly above the point in question.

A buoyant balloon kept from rising freely by means of a line secured to a point on the ground, as opposed to a free balloon. See kytoon.

A general term for atmospheric water in any of its forms, i.e. clouds, fog, hail, ice crystals, rain.