A wooden enclosure about sixteen feet square and eight feet high with a precipitation gauge at its center. The function of the fence is to minimize eddies around the gauge and thus insure a catch that is representative of the actual rainfall or snowfall.

A conically shaped, copper rain gauge shield.

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

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.

An instrument used for the determination of the electrical conductivity of the atmosphere.

A coating of ice, generally clear and smooth. formed by the freezing of supercooled water on a surface.

A recording weight barometer.

The condition of the atmosphere when the amount of water vapor present is the maximum possible at the existing temperature.

The state of the atmosphere, mainly with respect to its effects upon life and human activities. As distinguished from climate, weather consists of the short-term (minutes to months) variations of the atmosphere.

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.

Integrated Flood Observing and Warning System. National Weather Service flood warning program.

A halo phenomenon consisting of a horizontal circle passing through the moon, corresponding to the parhelic circle through the sun. Produced by reflection of moonlight from ice crystals.

In nautical terminology, a contraction for "weather glass" (a mercury barometer).

A vector term which includes both wind speed and wind direction.

Emission or transfer of energy in the form of electromagnetic waves or particles.

The ratio of the existing amount of water vapor in the air at a given temperature to the maximum amount that could exist at that temperature. Usually expressed in percent.

The process by which small particles suspended in a medium of a different refractive index diffuse a portion of the incident radiation in all directions. In scattering no energy transformation results, only a change in the spatial distribution of the radi ...

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

A type of photoelectric photometer used to measure high-altitude winds on the assumption that stellar scintillation is caused by atmospheric inhomogeneities being carried along by wind near the tropopause level.

The water volume within a specified portion of a stream channel.