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.

An aneroid barometer arranged so that the deflection of the aneroid capsule actuates a pen which graphs a record on a rotating drum. Sometimes called aneroidograph.

In folklore, a name for wind.

See evaporative opportunity.

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

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.

Same as marine rainbow.

A conically shaped, copper rain gauge shield.

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

A curve showing the variation of temperature with height in the free air. See lapse rate.

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

Precipitation caused by the ascent of moist air over an orographic barrier such as a Mountain range.

An instrument for recording global solar radiation.

A cup anemometer with its shaft mechanically coupled to a magneto.

An instrument for determining the direction from which radio waves approach a receiver. It may consist of a manually operated direction indicator, or it may use a servo system to position the antenna automatically in the direction of the incident waves.

The distance or length of flow of the air past a point during a given interval of time.

A common unit used in measurement of atmospheric pressure. Defined as that pressure exerted by a one-inch column of mercury at standard gravity and a temperature of 0'C.

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.