normal lapse rate

meteorology

Also known as: environmental lapse rate

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July 1, 2026

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The normal lapse rate in meteorology refers to the rate at which temperature decreases as you move upward through the Earth's atmosphere. This is also known as the environmental lapse rate. On average, the temperature drops by about 6.5 °C (11.7 °F) for every kilometer (0.6 miles) of altitude in the troposphere, the lowest layer of the atmosphere.1

This cooling occurs because as air rises, it encounters lower atmospheric pressure. This allows the air to expand, and this expansion uses energy, causing the air to cool down. This is known as adiabatic cooling. The lapse rate is crucial for meteorologists in forecasting weather phenomena like cloud formation and thunderstorms.21

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atmosphere
Convection
…free convection, occurs when the environmental lapse rate (the rate of change of an atmospheric variable, such as temperature or density, with increasing altitude) of temperature decreases at a rate greater than 1 °C per 100 metres (approximately 1 °F per 150 feet). This rate is called the adiabatic lapse…
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…free convection, occurs when the environmental lapse rate (the rate of change of an atmospheric variable, such as temperature or density, with increasing altitude) of temperature decreases at a rate greater than 1 °C per 100 metres (approximately 1 °F per 150 feet). This rate is called the adiabatic lapse…
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lapse rate
…air—commonly referred to as the normal, or environmental, lapse rate—is highly variable, being affected by radiation, convection, and condensation; it averages about 6.5 °C per kilometre (18.8 °F per mile) in the lower atmosphere (troposphere). It differs from the adiabatic lapse rate, which involves temperature changes due to the rising…
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…air—commonly referred to as the normal, or environmental, lapse rate—is highly variable, being affected by radiation, convection, and condensation; it averages about 6.5 °C per kilometre (18.8 °F per mile) in the lower atmosphere (troposphere). It differs from the adiabatic lapse rate, which involves temperature changes due to the rising…
Read More