The record of an aneroid barograph.

Anemometer which measures wind speed by the speed of rotation of 3 or 4 hemispherical or conical cups, each fixed to the end of a horizontal arm projecting from a vertical axis. See condenser-discharge anemometer, contact anemometer. Compare to bridled-cu ...

A hydrometeor consisting of an aggregate of microscopic and more-or-less hygroscopic water droplets suspended in the atmosphere. It reduces visibility to a lesser extent than fog. The relative humidity of mist is often less than 95 percent.

Pyrheliometer based on the comparison of the heating of two identical metal strips, one exposed to radiation, the other to a joule effect.

See sea-water thermometer, reversing thermometer.

The record or trace made by a microbarograph.

A reversing thermometer which is encased in a strong glass outer shell that protects it against hydrostatic pressure. Compare to unprotected thermometer.

NEXt Generation RADar. A NWS network of about 140 Doppler radars operating nationwide.

The older name for the Celsius temperature scale. Officially abandoned by international agreement in 1948, but still in common use.

Determination of the total amount of snow covering a watershed or a given region. Both depth and water content of the snow may be measured, and the results may be used to predict the amount of water that will be available after melting.

An instrument which automatically records the measurement of two or more meteorological elements.

An instrument for measuring angles of inclination. Used in conjunction with a ceiling light to measure cloud height at night.

The true freezing point of water. The temperature at which a mixture of air-saturated pure water and pure ice may exist in equilibrium at a pressure of one standard atmosphere.

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.

Instrument for measuring the mean intensity of glo global solar radiation (direct and diffuse) near the earth's surface in a specified time interval.

The general term for dry atmospheric suspensoids, including dust, haze, smoke. and sand. Compare to hydrometeor.

The difference between the air temperature and the dew-point. Also called dew-point deficit, dew-point depression.

Radiation with wavelengths greater than 4 microns. (In meteorology, same as infrared radiation.)

Value of soil moisture, expressed as a percentage of the mass of dry soil, below which a plant living in the soil dies by wilting.

An evaluation of upper air temperature, pressure, and humidity from radio signals received from a balloon- borne radiosonde.