Clouds are white because their water droplets or ice crystals are large enough to scatter the light of the seven wavelengths red, orange, yellow, green, blue, indigo, and violet , which combine to produce white light.
Why do clouds turn gray? Clouds are made up of tiny water droplets or ice crystals, usually a mixture of both. The water and ice scatter all light, making clouds appear white. If the clouds get thick enough or high enough all the light above does not make it through, hence the gray or dark look.
Also, if there are lots of other clouds around, their shadow can add to the gray or multicolored gray appearance.
Why do clouds float? A cloud is made up of liquid water droplets. A cloud forms when air is heated by the sun. As it rises, it slowly cools it reaches the saturation point and water condenses, forming a cloud. As long as the cloud and the air that its made of is warmer than the outside air around it, it floats! How do clouds move? Contrails are made by high-flying jet airplanes.
They are still clouds, though, because they are made of water droplets condensed from the water vapor in the exhaust of the jet engines. Weather prediction: Contrails can provide information about the layers of moisture in the sky. Mammatus clouds are actually altocumulus, cirrus, cumulonimbus, or other types of clouds that have these pouch-like shapes hanging out of the bottom.
The pouches are created when cold air within the cloud sinks down toward the Earth. Weather prediction: Severe weather might be on its way! Orographic clouds get their shape from mountains or hills that force the air to move over or around them. They can also be formed by sea breezes and often appear as lines where two air masses meet. Weather prediction: An early sign that the conditions might be right to form afternoon thunderstorms!
Lenticular clouds Lenticular clouds are shaped like lenses or almonds or They may get their shape from hilly terrain or just the way the air is rising over flat terrain. Weather prediction: None! Scientists have found that rapid growth and cooling at the tops of clouds are indicators of the potential for severe weather.
The ABI can show more detailed changes in cloud-top features, helping scientists assess the potential size and severity of a storm even before it reaches its peak! Cirrus Cirrus clouds are delicate, feathery clouds that are made mostly of ice crystals. Cirrostratus Cirrostratus clouds are thin, white clouds that cover the whole sky like a veil. Cirrocumulus Cirrocumulus clouds are thin, sometimes patchy, sheet-like clouds.
Altocumulus Altocumulus clouds have several patchy white or gray layers, and seem to be made up of many small rows of fluffy ripples. Altostratus Altostratus clouds are gray or blue-gray mid-level clouds composed of ice crystals and water droplets. Depending on the altitude, time of year, and vertical temperature structure of the troposphere, these clouds may be composed of liquid water droplets, ice crystals, or a combination of the two, including supercooled droplets i.
The two main type of mid-level clouds are altostratus and altocumulus. Altostratus clouds over Kentucky Altocumulus sunset 23 Nov. Altostratus clouds are "strato" type clouds see below that possess a flat and uniform type texture in the mid levels. They frequently indicate the approach of a warm front and may thicken and lower into stratus, then nimbostratus resulting in rain or snow. However, altostratus clouds themselves do not produce significant precipitation at the surface, although sprinkles or occasionally light showers may occur from a thick alto-stratus deck.
Altocumulus clouds exhibit "cumulo" type characteristics see below in mid levels, i. Like cirrocumulus , altocumulus may align in rows or streets of clouds, with cloud axes indicating localized areas of ascending, moist air, and clear zones between rows suggesting locally descending, drier air.
Altocumulus clouds with some vertical extent may denote the presence of elevated instability, especially in the morning, which could become boundary-layer based and be released into deep convection during the afternoon or evening. Low-level clouds:. Low-level clouds are not given a prefix, although their names are derived from "strato-" or "cumulo-", depending on their characteristics.
Low clouds occur below feet, and normally consist of liquid water droplets or even supercooled droplets, except during cold winter storms when ice crystals and snow comprise much of the clouds.
The two main types of low clouds include stratus , which develop horizontally, and cumulus , which develop vertically. Stratus clouds are uniform and flat, producing a gray layer of cloud cover which may be precipitation-free or may cause periods of light precipitation or drizzle.
Low stratus decks are common in winter in the Ohio Valley, especially behind a storm system when cold, dismal, gray weather can linger for several hours or even a day or two.
Stratocumulus NImbostratus. Stratocumulus clouds are hybrids of layered stratus and cellular cumulus, i. Stratocumulus also can be thought of as a layer of cloud clumps with thick and thin areas. These clouds appear frequently in the atmosphere, either ahead of or behind a frontal system.
Nimbostratus clouds are generally t hick, dense stratus or stratocumulus clouds producing steady rain or snow. In contrast to layered, horizontal stratus , cumulus clouds are more cellular individual in nature, have flat bottoms and rounded tops, and grow vertically.
In fact, their name depends on the degree of vertical development. For instance, scattered cumulus clouds showing little vertical growth on an otherwise sunny day used to be termed " cumulus humilis " or " fair weather cumulus ," although normally they simply are referred to just as cumulus or flat cumulus. A cumulus cloud that exhibits significant vertical development but is not yet a thunderstorm is called cumulus congestus or towering cumulus.
If enough atmospheric instability, moisture, and lift are present, then strong updrafts can develop in the cumulus cloud leading to a mature, deep cumulonimbus cloud, i. In addition, cloud electrification occurs within cumulonimbus clouds due to many collisions between charged water droplet, graupel ice-water mix , and ice crystal particles, resulting in lightning and thunder.
Cumulus clouds are all capable of producing some serious storms!!! Other interesting clouds:. Wall Cloud : A localized lowering from the rain-free base of a strong thunderstorm. The lowering denotes a storm's updraft where rapidly rising air causes lower pressure just below the main updraft, which enhances condensation and cloud formation just under the primary cloud base.
Wall clouds take on many shapes and sizes. Some exhibit strong upward motion and cyclonic rotation, leading to tornado formation, while others do not rotate and essentially are harmless.
Shelf Cloud : A low, horizontal, sometimes wedge-shaped cloud associated with the leading edge of a thunderstorm? Although often appearing ominous, shelf clouds normally do not produce tornadoes. Paducah, Ky Winchester, Ky. Fractus : Low, ragged stratiform or cumuliform cloud elements that normally are unattached to larger thunderstorm or cold frontal cloud bases.
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