NEXt Generation RADar. A NWS network of about 140 Doppler radars operating nationwide.

An instrument used to reveal but not necessarily measure the presence of an electrical quantity. It is used to display the output of a sensing element after suitable amplification and modification. Sometimes called display.

The direction, with respect to magnetic north, from which the wind is blowing. Distinguish from true wind direction.

Defect in the action of an aneroid barometer resulting in a sluggish adjustment of the index toward the correct reading when the barometer is subjected to a large and rapid change in pressure.

The statement that the viscosity of air is independent of the density of air.

See radar theodolite, radio direction-finder.

The stage on a fixed river gauge at which it is necessary to begin issuing warnings or river forecasts if adequate precautionary measures are to be taken before flood stage is reached.

The change in the measured transducer output caused by changes in ambient temperature. Usually expressed a percentage of full scale.

Same as marine rainbow.

Extended Binary Coded Decimal Interchange Code. A standard code used to represent data using 8 bits per character.

A halo consisting of a faint white circle passing through the Sun and running parallel to the horizon for as much as 360

A type of pressure-plate anemometer in which the plate, restrained by a stiff spring, is held perpendicular to the wind. The wind-activated motion of the plate is measured electrically. The natural frequency of this system can be made high enough so that ...

In folklore, a name for wind.

See evaporative opportunity.

The correctable part of the inaccuracy of an instrument.

The distance that an observer can see vertically into a surface-based obscuring phenomenon such as fog, rain, or snow. The distance estimate must be based upon ceiling balloon ascensions or ceiling light projector measurements.

A conically shaped, copper rain gauge shield.

Same as instrument shelter.

A point (or line) on a scale used for reference or comparison purposes. In calibration of meteorological thermometers, for example, the fiducial points are 100

A common type of liquid-inglass thermometer, used, in meteorology, in psychrometers and as a maximum thermometer.