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station modelclick to hear

Method of representing information collected by an observation station on a weather map using symbols and numbers.
station model air temperature wind direction present state of weather temperature of dew point type of low cloud pressure change barometric tendency sky coverage sea-level pressure station circle type of middle cloud type of high cloud wind speed

air temperature click to hear

Sensation of heat or cold (°F) measured using an open-air thermometer shielded from direct sunlight.

wind direction click to hear

Wind direction is indicated by the position of the wind shaft.

present state of weather click to hear

Type of precipitation (present weather) noted at the moment of observation.

temperature of dew point click to hear

Temperature (°F) at which water vapor in the air begins to condense; it is used to calculate humidity in the air.

type of low cloud click to hear

Type of cloud observed between ground level and an altitude of 6,500 feet.

pressure change click to hear

Positive or negative value that corresponds to the difference between the pressure reading and sea-level pressure; it is expressed in inches of mercury.

barometric tendency click to hear

Variation in atmospheric pressure during the three hours preceding observation.

sky coverage click to hear

Proportion of the sky covered with cloud.

sea-level pressure click to hear

Reference pressure that corresponds to the pressure observed at sea level; it is expressed in inches of mercury.

station circle click to hear

Circle on a weather map that represents an observation station; displayed around the circle is the information collected by the station.

type of middle cloud click to hear

Type of cloud observed at altitudes between 6,500 and 20,000 feet.

type of high cloud click to hear

Type of cloud observed at altitudes higher than 20,000 feet.

wind speed click to hear

Wind speed is indicated by barbs and pennants whose values must be added.