Integrated Flood Observing and Warning System. National Weather Service flood warning program.

Temperature of equilibrium between the liquid and vapor phases of a substance at a given pressure.

Any one of six gases, helium, neon, argon, krypton, xenon, and radon, all of whose shells of planetary electrons contain stable numbers of electrons such that the atoms are chemically inactive.

An instrument for recording ocean waves. Most recorders are designed for recording wind waves, that is waves of periods up to about 25 seconds, but some are designed to record waves of longer periods such as tsunamis or tides.

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

The record of a 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 liquid-in-glass or liquid-in-metal thermometer using mercury as the liquid.

Very generally, any moving- stream of air. It has no particular technical connotation.

Same as wind sock.

A type of cooling-power anemometer based upon the principle that the time constant of a thermometer is a function of its ventilation.

An instrument for measuring differences in electric potential.

A unit of pressure which directly expresses the force exerted by the atmosphere. Equal to 1000 dynes/cm2 or 100 pascals.

An empirical curve relating stream discharge or stage at a point on a stream to discharge or stage at one or more upstream points and, possibly. to other parameters. Also called stage relation.

Same as river gauge.

Wind with a speed between 28 and 33 knots (32 and 38 mph); Beaufort scale number 7.

An instrument for measuring the extinction coefficient in water.

A hygrometer which determines the amount of precipitable moisture in a given region of the atmosphere by measuring attenuation of radiant energy caused by the absorption bands of water vapor.

The value of the quantity measured, as indicated or otherwise provided by a measuring instrument.

See hydrologic accounting.