The upper surface of a column of liquid.

A water-temperature thermometer provided with an insulated container around the bulb. It is lowered into the sea on a line until it has had time to reach the temperature of the surface water, then withdrawn and read. The insulated water surrounding the bu ...

A system in which radar techniques are used to determine the range, elevation, and azimuth of a radar target carried a!oft by a radiosonde, so that wind data may be obtained along with the other meteorological data.

Same as atmometer.

Of or pertaining to the air, atmosphere, or aviation. Also, same as antenna.

Winds from the four cardinal points of the compass; that is, north, east, south, and west winds.

As used by the U.S. Army Corps of Engineers, the departure (in

Ragged low clouds, usually stratus fractus. Most often applied when such clouds are moving rapidly beneath a layer of nimbostratus.

An instrument used to measure the water vapor content of the air. A type of hygrometer. It consists of a wet-bulb and a dry-bulb thermometer. See aspiration psychrometer, Assmann psychrometer. hygrodeik, sling psychrometer.

Rate of wind movement in distance per unit time.

Same as geostrophic wind level.

In Jeffreys' classification, a wind for which the pressure force exactly balances the viscous force, in which the vertical transfers of momentum predominate.

An instrument for the measurement of the rate of ice accretion on an unheated body.

United Kingdom forecast model. (Available via AccuWeather.com Professional.)

The total luminous flux received on a unit area of a given real or imaginary surface, expressed in such units as the foot-candle, lux, or phot.

An instrument that automatically records pressure and temperature.

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

The atmospheric pressure computed using station elevation as the reference datum level. Station pressure is usually the base value from which sea level pressure and altimeter setting are determined.

Same as constant-level balloon.

Snow shower, particularly of a very light and brief nature.