The depth of water that would result from the melting of snow or ice, assuming measurement on a horizontal surface and no infiltration or evaporation.

A form of data transmission in which the bits of each character are sent one at a time along a single communication path. Compare to parallel data transmission.

The gravity flow of water within soil.

An instrument resulting from the combination of a thermograph and a hygrograph and furnishing, on the same chart, simultaneous time recording of ambient temperature and humidity.

See hurricane beacon.

A weakly colored lunar halo identical in form and optical origin to the solar parhelion.

The volume of liquid water evaporated per unit area in unit time. usually measured as the depth of liquid water lost per unit time from the whole area.

A wind (or component thereof) directed down the slope of an incline and caused by greater air density near the slope than at the same levels some distance horizontally from the slope. Also called drainage wind and sometimes called katabatic wind.

Precipitation caused by the ascent of moist air over an orographic barrier such as a Mountain range.

A device for obtaining a continuous record of stage at a point on a stream. The most common recorders consist of a float-actuated pen which traces a record on a clock driven chart.

A thermograph in which ventilation is provided by a suction fan.

Abbreviation for radio frequency.

Name applied to a class of instruments which measure the liquid content of the atmosphere.

The group of bits which a computer processes as a unit; often, 8 bits.

The atmospheric pressure at the level of the barometer. May or may not be the same as station pressure.

See instrument error, observational error. random error, standard error, systematic error.

Any twelve-month period, usually selected to begin and end during a relative dry season. Used a basis for processing streamflow and other hydrologic data. The period from October 1 to September 30 is widely used in the U.S.

The actual lifting force of an inflated balloon, usually expressed in grams.

Any source of radiant energy, especially electromagnetic energy.

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