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  2. Weather forecasting - Wikipedia

    en.wikipedia.org/wiki/Weather_forecasting

    Measurements of barometric pressure and the pressure tendency (the change of pressure over time) have been used in forecasting since the late 19th century. [66] The larger the change in pressure, especially if more than 3.5 hPa (2.6 mmHg), the larger the change in weather can be expected.

  3. Atmospheric pressure - Wikipedia

    en.wikipedia.org/wiki/Atmospheric_pressure

    Atmospheric pressure, also known as air pressure or barometric pressure (after the barometer), is the pressure within the atmosphere of Earth. The standard atmosphere (symbol: atm) is a unit of pressure defined as 101,325 Pa (1,013.25 hPa ), which is equivalent to 1,013.25 millibars , [ 1 ] 760 mm Hg , 29.9212 inches Hg , or 14.696 psi . [ 2 ]

  4. Station model - Wikipedia

    en.wikipedia.org/wiki/Station_model

    On the top right corner of the model for a surface weather map is the pressure, showing the last two integer digits of the pressure in millibars, or hectopascals, along with the first decimal. For instance, if the pressure at a certain location is 999.7 hPa, the pressure portion of the station model will read 997.

  5. Prognostic chart - Wikipedia

    en.wikipedia.org/wiki/Prognostic_chart

    Manual prognostic charts depict tropical cyclones, turbulence, weather fronts, rain and snow areas, precipitation type and coverage indicators, as well as centers of high and low pressure. [6] Within the United States, these type of maps are generated by the Hydrometeorological Prediction Center , [ 7 ] the Storm Prediction Center , [ 5 ] the ...

  6. Outline of meteorology - Wikipedia

    en.wikipedia.org/wiki/Outline_of_meteorology

    Barograph – an aneroid barometer that records the barometric pressure over time and produces a paper or foil chart called a barogram; Barometer – an instrument used to measure atmospheric pressure using either water, air, or mercury; useful for forecasting short term changes in the weather

  7. Surface weather analysis - Wikipedia

    en.wikipedia.org/wiki/Surface_weather_analysis

    A surface weather analysis for the United States on October 21, 2006. By that time, Tropical Storm Paul was active (Paul later became a hurricane). Surface weather analysis is a special type of weather map that provides a view of weather elements over a geographical area at a specified time based on information from ground-based weather stations.

  8. Atmospheric model - Wikipedia

    en.wikipedia.org/wiki/Atmospheric_model

    A 96-hour forecast of 850 mbar geopotential height and temperature from the Global Forecast System. In atmospheric science, an atmospheric model is a mathematical model constructed around the full set of primitive, dynamical equations which govern atmospheric motions.

  9. Barometer - Wikipedia

    en.wikipedia.org/wiki/Barometer

    When atmospheric pressure is measured by a barometer, the pressure is also referred to as the "barometric pressure". Assume a barometer with a cross-sectional area A, a height h, filled with mercury from the bottom at Point B to the top at Point C. The pressure at the bottom of the barometer, Point B, is equal to the atmospheric pressure.