General name for an instrument designed to measure the vertical component of the wind speed. See anemoclinometer.

A term used to describe a sensor (or sensors), the associated transducer(s), and the data readout or recording device.

A river gauge in which a weight suspended on a wire is lowered to the water surface from a bridge or other overhead structure to measure the distance from a point of known elevation to the water surface.

Fine dust or salt particles dispersed through a portion of the atmosphere; a type of lithometer. The particles are so small they cannot be felt or seen with the naked eye. Many haze formations are caused by the presence of an abundance of condensation nuc ...

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

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

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 current meter consisting of six conical cups, mounted around a vertical axis, which rotate and generate a signal with each rotation. Tail vanes and a heavy weight stabilize the instrument.

Conditions to which a device is subjected, not including the variable measured by the device. See normal operating conditions, reference operating conditions.

The total of direct solar radiation and diffuse sky radiation received by a unit horizontal surface. Global radiation is measured by pyranometers.

The play or loose motion in an instrument due to the clearance existing between mechanically contacting parts.

The amount of sky covered or concealed by clouds or obscuring phenomena. It is reported in tenths, so that 0.0 indicates a clear sky and 1.0 (or 10/10) indicates a completely covered sky. The following classifications are used in aviation weather observat ...

The component of the radiosonde which includes the modulating blocking oscillator and the radiofrequency carrier oscillator.

Same as ceiling light.

Same as rain-intensity gauge.

Solar and terrestrial radiation directed downwards (towards the earth's surface); incoming radiation.

A rain gauge which automatically records the amount of precipitation collected, as a function of time.

An instrument for measuring the frost point of the atmosphere.

A sudden brief increase in the speed of the wind, followed by a lull or slackening. Compare to peak gust.

The processing of the form or mode of a signal so as to make it intelligible to, or compatible with, a given device.