AIR DENSITY The ratio of the mass of a substance to the volume it occupies. In oceanography, it is equivalent to specific gravity and represents the ratio of the weight of a given volume of sea water [..]

See barometric pressure

The pressure exerted by the atmosphere as a consequence of gravitational attraction exerted upon the "column" of air lying directly above the point in question. The measurement is ex [..]

   A system of estimating and reporting wind speeds. It is based on the Beaufort Force or Number, which is composed of the wind speed, a descriptive term, and the visible effects upon land objects and [..]

The inaccuracy that the manufacturer permits when the unit is calibrated in the factory.

For a given cloud or cloud layer. The lowest level in the atmosphere at which the air contains a perceptible quantity of cloud particles. The weather station estimates the cloud base on temperature an [..]

A cooling degree day is given for each degree that the daily mean temperature departs above the baseline of 75 degrees a given temperature It is used to estimate the energy requirements, and is an ind [..]

The temperature to which a sample of air must be cooled, while the mixing ratio and barometric pressure remain constant, in order to attain saturation by water vapor. When this temperature is below O° [..]

A sudden significant increase in or rapid fluctuations of wind speed. Peak wind must reach at least 16 knots (18 miles per hour) and the variation between peaks and lulls is at least 10 knots (11.5 mi [..]

The combination of air temperature and humidity that gives a description of how the temperature feels. This is not the actual air temperature.