Nested Grid Model generated every 12 hours by NCEP.

Random Access Memory. The memory of a computer which can be read and written into at any location without passing through preceding locations.

See radar theodolite, radio direction-finder.

A halo consisting of a faint white circle passing through the Sun and running parallel to the horizon for as much as 360

The temperature at which a solid substance undergoes fusion, i.e. melts, changes from solid to liquid form. All substances have their characteristic melting points. For very pure substances the temperature range over which the process of fusion occurs is ...

Solar radiation scattered by particles in the atmosphere.

An instrument used to reveal but not necessarily measure the presence of an electrical quantity. It is used to display the output of a sensing element after suitable amplification and modification. Sometimes called display.

Routine broadcast of meteorological information for aircraft in flight.

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

Same as marine rainbow.

A vector term which includes both wind speed and wind direction.

Extended Binary Coded Decimal Interchange Code. A standard code used to represent data using 8 bits per character.

Occupational Safety and Health Administration. A regulatory office of the U.S. Department of Labor.

The lowest level at which the wind becomes geostrophic in the theory of the Ekman spiral. Also called gradient wind level.

A point (or line) on a scale used for reference or comparison purposes. In calibration of meteorological thermometers, for example, the fiducial points are 100

Same as dropsonde.

The correctable part of the inaccuracy of an instrument.

The transmission of data collected at a remote location over communications channels to a central station.

A flower-like diagram indicating the relative frequencies of different wind directions for a given station and period of time.

A conically shaped, copper rain gauge shield.