A type of pressure-tube anemometer, named after the inventor.

Pertaining to measurements or devices in which the output vanes in discrete steps, i.e. on-off or pulse signals. Compare to analog.

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

A graphical representation of a frequency distribution. The range of the variable is divided into class intervals for which the frequency of occurrence is represented by a rectangular column. The height of the column is proportional to the frequency of ob ...

A nephoscope in which the motion of the cloud is observed by its reflection in a mirror.

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

For a given locality and month, an empirical expression devised for the purpose of classifying climates numerically on the basis of precipitation and evaporation.

An instrument which measures the transmissivity of the atmosphere between two points for the determination of visual range.

An Instrument used to determine dew point.

Instrument which measures and records the amount of evaporation over time.

Anemometer which measures wind speed by measuring the degree of cooling of a metal film heated by an electric current. A type of cooling-power anemometer.

An instrument used to measure the amount of dew formed on a given surface.

Transistor-Transistor Logic.

The audio-frequency signal transmitted by the Diamond-Hinman radiosonde when the baroswitch pen passes each fifteenth contact of the commutator, up to a number determined by the design of the commutator, and each fifth contact thereafter. This signal is t ...

Hygrometer in which the dew (frost) point is determined by observing the temperature of an artificially cooled surface at the moment at which dew (frost) first appears on it.

An instrument which measures the instantaneous rate at which rain is falling on a given surface. Also called a rate-of-rainfall gauge.

A system of physical units based upon the use of the meter, the metric ton (106 grams), and the second as elementary quantities of length, mass, and time, respectively.

The direction toward which the wind is blowing; with the wind.

An aviation weather forecast for a specific flight.

The closeness of agreement among a number of consecutive output values measuring the same input value under the same operating conditions, approaching from the same direction. Usually measured as nonrepeatability but expressed as repeatability, a percenta ...