Wind with a speed between 11 and 16 knots (13 and 18 mph); Beaufort scale number 4.

A self-recording instrument used on aircraft for the simultaneous recording of atmospheric pressure, temperature, and humidity.

A basic equation in daytime visual range theory, relating the apparent luminance of a distant black object, the apparent luminance of the background sky above the horizon, and the extinction coefficient of the atmosphere, or the air layer near the ground. ...

The unit of force in the centimeter-gram-second system of physical units, i.e. one gm cm per sec2, equal to 7.233 x 10-5 poundal.

A large body of air having similar horizontal temperature and moisture characteristics.

pattern barometer-Mercurial barometer with a fixed scale and cistern and which therefore requires only one adjustment before each reading.

Navy Operational Global Atmospheric Prediction System. A global meteorological model operated by the Department of Defense.

Readily taking up and retaining moisture.

Electromagnetic radiation lying in the wavelength interval between 0.8 micron and I millimeter. At the lower limit of this interval, the infrared radiation spectrum is bounded by visible radiation, while on its upper limit it is bounded by microwave radia ...

A photometer which measures the intensity of radiation as a function of the frequency (or wavelength) of the radiation.

The level at which ice crystals and snowflakes melt as they descend through the atmosphere.

A small pointer extending downward from the top of the cistern of a Fortin barometer. The level of the mercury in the cistern is adjusted so that it just comes in contact with the end of the pointer, thus setting the zero of the barometric scale.

Lacking a relationship to a time base or clock. In asynchronous communications, individual data characters are sent at an arbitrary rate.

That part of snow melt that reaches stream channels as runoff.

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

Precipitation of very small, white opaque particles of ice, fairly flat or elongated, with diameters less than 1 mm. The solid equivalent of drizzle.

A measure of the attenuation due to scattering, of light as it traverses a medium containing scattering particles.

A precipitation amount of less than 0.005 inches. Also, the record made by any self-registering instrument.

A refraction phenomenon similar to a parahelion, but occurring generally at a distance of 120

The portion of the strearnflow during any month or year derived from precipitation in previous months or years.