Cumulus humilis cloud
Encyclopedia
Cumulus humilis is a low to middle cloud with small vertical extent (Family D1) that is commonly referred to as "fair weather cumulus
". In hot countries and over mountainous terrain these clouds occur at up to 6000 meters altitude, though elsewhere they are typically found lower.
They are formed by rising warm air that has been heated by the ground, which in turn has been heated by the sun. They have a limited depth (technically known as showing no significant vertical development). This indicates that the temperature
in the atmosphere above them either drops off very slowly or not at all with altitude (see Lapse rate
). While cumulus humilis may be accompanied by other cloud
types, when they appear in a clear sky
(see picture), they are an indicator of pleasant weather for the next several hours. Though at times, these clouds collapse into stratocumulus clouds, and cover much of the sky.
Air below the cloud base can be quite turbulent, giving occupants of light aircraft an uncomfortable ride. To avoid turbulence
where such clouds are present, pilots may climb above the cloud tops. However, glider
pilots actively seek out the rising air to gain altitude.
in the afternoon or evening. Cumulus humilis clouds are not rain clouds but could show an impending storm in the future.
Cumulus cloud
Cumulus clouds are a type of cloud with noticeable vertical development and clearly defined edges. Cumulus means "heap" or "pile" in Latin. They are often described as "puffy" or "cotton-like" in appearance. Cumulus clouds may appear alone, in lines, or in clusters...
". In hot countries and over mountainous terrain these clouds occur at up to 6000 meters altitude, though elsewhere they are typically found lower.
They are formed by rising warm air that has been heated by the ground, which in turn has been heated by the sun. They have a limited depth (technically known as showing no significant vertical development). This indicates that the temperature
Temperature
Temperature is a physical property of matter that quantitatively expresses the common notions of hot and cold. Objects of low temperature are cold, while various degrees of higher temperatures are referred to as warm or hot...
in the atmosphere above them either drops off very slowly or not at all with altitude (see Lapse rate
Lapse rate
The lapse rate is defined as the rate of decrease with height for an atmospheric variable. The variable involved is temperature unless specified otherwise. The terminology arises from the word lapse in the sense of a decrease or decline; thus, the lapse rate is the rate of decrease with height and...
). While cumulus humilis may be accompanied by other cloud
Cloud
A cloud is a visible mass of liquid droplets or frozen crystals made of water and/or various chemicals suspended in the atmosphere above the surface of a planetary body. They are also known as aerosols. Clouds in Earth's atmosphere are studied in the cloud physics branch of meteorology...
types, when they appear in a clear sky
Sky
The sky is the part of the atmosphere or outer space visible from the surface of any astronomical object. It is difficult to define precisely for several reasons. During daylight, the sky of Earth has the appearance of a pale blue surface because the air scatters the sunlight. The sky is sometimes...
(see picture), they are an indicator of pleasant weather for the next several hours. Though at times, these clouds collapse into stratocumulus clouds, and cover much of the sky.
Air below the cloud base can be quite turbulent, giving occupants of light aircraft an uncomfortable ride. To avoid turbulence
Turbulence
In fluid dynamics, turbulence or turbulent flow is a flow regime characterized by chaotic and stochastic property changes. This includes low momentum diffusion, high momentum convection, and rapid variation of pressure and velocity in space and time...
where such clouds are present, pilots may climb above the cloud tops. However, glider
Gliding
Gliding is a recreational activity and competitive air sport in which pilots fly unpowered aircraft known as gliders or sailplanes using naturally occurring currents of rising air in the atmosphere to remain airborne. The word soaring is also used for the sport.Gliding as a sport began in the 1920s...
pilots actively seek out the rising air to gain altitude.
Forecast
If these clouds are present in the morning it is a sign of an unstable atmosphere. Larger clouds and possibly thunderstorms could form throughout the day to cause bad or severe weatherSevere weather
Severe weather phenomena are weather conditions that are hazardous to human life and property.- Examples Include :Severe weather can occur under a variety of situations, but three characteristics are generally needed: a temperature or moisture boundary, moisture, and , instability in the...
in the afternoon or evening. Cumulus humilis clouds are not rain clouds but could show an impending storm in the future.