Apparatus designed to measure the amount of precipitation falling in the form of snow. The device determines the weight of the snow or the volume of water after the snow melts.

The minimum temperature shown by a minimum thermometer exposed in an open situation with its bulb at the level of the tops of the grass blades of short turf.

A device used to switch electrical current at a selectable setpoint temperature.

Same as fogbow.

Same as altimeter setting.

An instrument which determines the altitude of an object with respect to a fixed level. There are two general types of altimeters: (a) the pressure altimeter, which gives an approximate measure of altitude from a pressure measurement and an assumed standa ...

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

A unit of mass numerically equal to the molecular weight of the substance. The gram-mote or gram-molecule is the mass in grams numerically equal to the molecular weight, i.e. a gram-mole of oxygen is 32 grams.

A hygrometer based upon the diffusion of water vapor through a porous membrane.

A device used on certain types of instruments to prevent unwanted radiation from affecting the measurement of a quantity. Also called solar radiation shield.

A local variation of the wind vector or any of its components in a given direction.

Temperature assumed by an unsaturated air parcel when brought adiabatically to a standard pressure (1,000 mb).

See calorie.

The record or trace made by a microbarograph.

A wind blowing in the same direction as the heading of a moving object. thus assisting the object's intended progress. The opposite of a head wind.

The inherent imprecision of a given process of measurement, the unpredictable component of repeated independent measurements of the same object under sensibly uniform conditions.

Balance of the water resources of a region, comparing precipitation and inflow with outflow, evaporation, and accumulation.

The height at which the maximum wind speed occurs, determined in a winds-aloft observation.

Winds which, over a small area, differ from those which would be appropriate to the general pressure distribution.

in United States weather observing practice, the highest "instantaneous" wind speed recorded at a station during a specified period, usually the 24-hour observation day. Therefore, a peak gust need not be a true gust of wind.